Fridge Brilliance:
- The lineup of the altered Justice League makes perfect sense in the context of the plan to let Lex hijack Superman's body through nanomachines and subvert it. Every hero who's missing is someone who would have the capability to be a serious threat to the plan's success, either by being able to seriously hurt Lex as Superman, having time travel capability, or being able to figure out that the League was being subverted even if their circumstances were also altered.
- Diana/Wonder Woman isn't present (Circe took up the name instead) because she has the Lasso of Truth. All she'd need is a moment of suspicion and a decent opportunity, and she could blow the plan wide open with irrefutable proof.
- The Flash is replaced by Inertia, which has the double bonus of Inertia not retaining Barry or Wally's strong moral code, and the different way his powers work (essentially, he slows time down around him instead of speeding himself up) means that he can't time-travel like the original Flashes could through the Speed Force. The League has someone with the tactical advantages of super speed, but one that cannot undo the conspirator's alterations even if he wanted to.
- Martian Manhunter is replaced by his evil brother (who, unlike J'onn, is fine with playing along) because as a Martian, J'onn is telepathic. He'd realize something was amiss immediately.
- Batman is replaced by the Question (who doesn't get an entry due to his Ambiguous Situation), because Batman is the world's greatest detective. Keeping him would run the risk of him inevitably putting the pieces together and figuring out a plan to Set Right What Once Went Wrong... which happens anyway when Jack takes up the mantle, but nothing's perfect.
- Captain Marvel is not present (Black Adam exists, but is an associate who mostly focuses on ruling Kahndaq). He has the Wisdom of Solomon to figure out that something's wrong, and his powers run on magic, which is traditionally one of Superman's greatest weaknesses. As Lex took over Superman's body, he couldn't have that.
- Hawkgirl is the C-List Fodder Vanessa Kingsbury because the Nth metal she uses is another thing that can bypass Superman's Kryptonian invulnerability. And because Kingsbury isn't Thanagarian, she doesn't have any access to Nth metal aside from her issued mace, severely limiting the threat she poses.
- Oliver Queen remains mostly the same because he's a Badass Normal without Batman's almost superhumanly keen mind, and no gimmicks that could pose a threat to Lex as Superman.
