Whatever the case, Ahnjayla has taken the title of "Wonder Woman", intending to use the fame and adoration that comes with it to satiate her hedonistic desires. Ahnjayla has taken the "Diana Prince" identity too, for when she simply wants to indulge privately. Ahnjayla doesn't respect the laws of Amazons or Men, but does have a personal honor code. She has no problem killing those opposing her in any way, nor executing those she defeats, but she cared about her public perception even before becoming Wonder Woman, and needs approval now more than ever. So she limits her targets to those she knows are criminals by the standards of men.
Why does she publicly call them out while lacking evidence? Ahnjayala was part of the criminal underworld before she was Wonder Woman. She knows who they are and what they're up to all too well. She's used to ratting them out to save herself from Diana and threatening to for blackmail, but did all that in private. She hasn't gotten used to the public stage yet. And in Amazon culture people challenged tend to meet their opponents head on. Even though the criminals of man's world are not so quick to confront her, some habits are hard to break.
Why does Ahnjayla blow up over her own designed doll and costume? Because unlike every other Amazon Ahnjayla prefers to cover herself from head to toe in the finest fashions and styles. She's used to intimidating and scamming her way to what she wants, but seduction and Sex Sells are still new concepts to her that a newly acquired employee of Themyscira Industries introduced her to. The allure of more revenue was enticing, and she of course has to keep up the illusion that she's Diana, who would wear something that stupid without hesitation in Ahnjayla's mind, but Ahnjayla has started to regret the decision.
And why can't anyone tell? The sisters are of similar size and have similar sounding voices. Ahnjayla doesn't act like Diana, but likely knows many things only Diana "should" know, and Diana never told anyone about her criminal sister because she was too ashamed. Ahnjayla herself didn't let knowledge of being related to such boring goody patriotic immigrant spread among the criminal underworld because she was equally ashamed! So all Ahnjayla has to do is disguise her facial features. Some hair dye, color contacts, some magical TV latex for her nose, lips and cheek bones, and most people are none the wiser. Except there might be someone who knows about the real Wonder Woman's evil sister. Some of Ahnjayla's surviving criminal cohorts may have seen the two together. Future episodes could deal with their attempts extort Themyscira Industries under threat of releasing the information and exposing Ahnjayla for what she really is.
The real Diana of Themyscira has been a thorn in Doctor Cyber's side though, severely disrupting her business. Doctor Cyber was able to blackmail Diana into keeping quiet and out of her affairs, however, and is now using both the Diana Prince and Wonder Woman identities to rebuild her finances with a more legal front, with a more public friendly face. This Cyber is somewhat of a Composite Character, having some of her Post Crisis cybernetic implants to duplicate some of Diana's powers even without her Powered Armor, but even with all of her technology Cyber can't duplicate everything like the lasso of truth and invisible jet, and she doesn't have so much on Diana to get Diana to give Cyber everything.
Doing her best to maintain Wonder Woman's image, that's part of the deal. Employing Diana's friends in Themyscira Industries is also part of the deal. At times Clyvia lets her frustrations become known, but she dare not violate the deal lest Diana come after Clyvia again. Why can no one tell Clyvia from Diana? As long as Clyvia sticks to her end of the deal Diana helps Cylvia maintain the illusion through advice. When it gets too hard and Cyber is on the brink of a breakdown she relaxes as "Diana Prince" to recharge.
And Veronica Cale? Cylvia Cyber is the one who got Veronica Cale started. But now that Cyber is a "legal" corporate "super hero" Veronica Cale is a loose end who could jeopardize Cyber's new operation. Cale had to be eliminated before she figured out too much.
Panthea's plot likely wouldn't have gone very well regardless, but she specifically attributed her failure to Diana's intervention. In the comics Panthea was imprisoned for good, but not here! Here she waited until Diana had returned to Paradise Island, or perhaps had left the planet altogether on some indeterminately long mission. That's when she struck. As a brilliant scientist who already demonstrated the ability to alter and remove illusions, creating her is a natural progression for Panthea. She somehow gathers enough resources to conceal her escape from prison and disguise herself as Wonder Woman.
The United States is not Panthea's culture though. She cannot so easily rally people to her cause even in the guise of a beloved public figure. She realizes that money means more in USA than charisma or scientific brilliance, so she decides to use her position as Wonder Woman to create Themyscira Industries. The firm ultimately exists to advance Panthea's research and her political ambitions. Motive Decay has kicked in though. Panthea's too obsessed about proving she is a "better" Wonder Woman than Diana. As a functionally immortal Amazon, Panthea believes she has plenty of time to get it out of her system and still achieve all her original goals, but had the pilot been picked up, future episodes would have had shown Panthea underestimated Diana's dedication to "Man's World". Diana would return ahead of Panthea's schedule and force Panthea to hasten her plans.
But why does no one at least suspect Wonder Woman's being impersonated? As long as anyone outside of Paradise Island has known Diana, Panthea probably knew her longer and better. They notice some disturbing changes, but they all are inline with things they think they know about Wonder Woman. Things most of her friends hoped she wouldn't come to, but were prepared for. Panthea was willing to get her own Amazon cohorts that she had known even longer than Diana killed just to advance her goals, so excessively beating, torturing and killing some Americans doesn't phase her. Panthea doesn't respect the law because she ultimately plans on establishing her own. Panthea's rant about Wonder Woman's image and reputation is just her venting about her hatred of Diana, which only grew as she bided her time in prison.
And Panthea's going after Veronica Cale specifically because she wants Cale's research and developments for herself. But she is legitimately disgusted with Cale's operation on top of that. Panthea sees promise in Veronica's findings, but finds the woman herself to be sloppy and shortsighted. She doesn't care about loss of life in of itself, but doesn't believe it was necessary in this case, and definitely finds the human trafficking unneeded. To Panthea, Veronica Cale is a weaker, stupider Queen Hippolyta.
In the comic strip Wonder Woman is at one point defeated, captured and impersonated by a mercenary known as Lady Steel. First, Lady Steel claims to be able to charge high fees simply by advertising herself as the perfect counter to Wonder Woman. Secondly, Lady Steel does such a good job posing as Wonder Woman that Superman, who in this comic can determine if a person is lying or not by their heart beat, has x-ray vision that can see through disguises and has experienced the physical abilities of the real Wonder Woman first hand, cannot tell Lady Steel is an imposter until the real Wonder Woman escapes and he's able to hear her voice a few minutes after Lady's Steel's. Lady Steel runs a mercenary company with at least one boarder crossing firearm smuggler and an international spy ring as regular clients. If any version of Wonder Woman was going to run a public business based off her name value and physical prowess, a Wonder Woman impersonated by a Lady Steel would have to be among the top five candidates. Furthermore, Lady Steel's disguise remained intact in battle with Superman, and no matter how well Wonder Woman's friends think they know her, no matter what lengths Lady Steel has to go to in pursuit of criminals, nothing seen in the pilot comes close to Superman. People likely have noticed Wonder Woman's drastic change in personality, but just like Superman they won't be able to spot the imposter until the real things shows herself.
The traditional inconsistencies? Lady Steel likely determined Diana Prince was Wonder Woman's secret identity, but doesn't know anything about Diana Prince besides what Wonder Woman's friends tell her. Why is she so uncomfortable with her own costume, one her own mother had made for her, one from a culture that used to parade around with one boob exposed before settling down on Paradise Island? Because Lady Steel would otherwise be wearing something more metallic and intimidating. Her rant about Wonder Woman's "perfect" features and public behavior? Resentment over things she can't change without blowing her cover. I Have Boobs, You Must Obey!? When Superman did find out Lady Steel was an imposter, she tried to seduce him, rather poorly at that. Brutality towards criminals? Lady Steel is a Smug Super mercenary, one who enjoys nothing more than crushing people with her bare hands. And the villains of the pilot? Pathetic amateurs who deserve what they get. Lady Steel likely has special disdain for Veronica Cale, who she would view as poser at best(alternatively, Cale was simply an aggravating client). She also can't duplicate the magical powers of the real Wonder Woman's lariats, and really wouldn't want to touch the lasso of truth, lest she be forced to come clean. Disrespect for the law? Lady Steel willingly worked for at least two cabals willing to subvert governments and start wars. Rude to her own employees and so called friends? Lady Steel ran her own company largely through threat and intimidation.
In this story Lady Steel was simply allowed to attempt to tarnish Wonder Woman's reputation without the real one arriving in time to clear things up. She likely has turned the other superheroes on Wonder Woman, but found the general public, international community and Diana's inner circle of friends much more forgiving than expected. Likely because one client, The International Spy Ring, were not able to successfully deceive Superman like she was. He likely still stopped them in this setting. With the international spy ring agents likely confessing their activities to various international authorities, including dealings with Lady Steel's mercenary company, Lady Steel likely found it more profitable to pretend to be Wonder Woman. To claim to have defeated Lady Steel and her soldiers while repurposing the company as Themyscira Industries.
The real Wonder Woman likely never escaped in this continuity, but probably wasn't killed either, as Lady Steel planned to do that after turning the world against her, which she obviously failed to do. Wonder Woman is probably still in captivity, always bound in the lasso of persuasion and visited by Lady Steel when she needs information to preserve the ruse, explaining why Lady Steel doesn't use the lariat that would be "safe" for her (The lasso of persuasion was also the one Wonder Woman brought while investigating the arms smugglers). Had the pilot been picked up there would eventually be some flash back episodes detailing Wonder Woman's arrival in "Man's World" to the rise of Themyscira Industries before she escapes and seeks to get her life back from Lady Steel.