André the Giant wasn't always the lumbering behemoth we know from the late 80s— in his youth, he could execute dropkicks and move fairly fast for his size. However, by the time he signed up with the WWF, age and problems with acromegaly had forced him to slow down.
Samoa Joe is a rare real-life example. Any near-300-pounder who can run rings around TNA's X Division, which is made up of Speedsters, can definitely call himself Acrofatic. Even more impressive, he often uses Enziguris, a move whose largest practitioner has traditionally been Chris Jericho, who weighs barely 220 pounds.
Big Van Vader. 450-pound men usually don't do moonsaults.
Big Show used to use moonsaults as part of his move-set when he was known as The Giant in WCW. Unsurprisingly, nobody wanted to take one from him. Not even the 6'11" Kevin Nash. He even speaks about this on an episode of WWE Tough Enough — saying that even a big guy like him needs to be athletic.
American Balloon. Obese dude doing the sky twister press. Seriously.
The late Bam Bam Bigelow often did cartwheels in the ring and one of his signature moves was a moonsault off the top turnbuckle. The reason why Bigelow is considered one of the most underrated wrestlers of all time is due to his ability to pull off moves that were normally done by cruiserweights.
Hugh Morrus and The Blue Meanie (before his weight loss). Both of these guys used moonsaults for their finishers.
Dusty Rhodes was so fat that he should have worn a bra, but still was amazingly agile. He lampshaded this in his "Hard Times" promo.
Born Windham Rotunda, Husky Harris used the Red Baron "The Army Tank with the Ferrari Engine" and has quite the speed and vertical leap. Even with some weight loss, he retained the speed with some added blood lust following his repackaging as Bray Wyatt.
Jerry 'Crusher' Blackwell. A 472-pound man who could effectively execute dropkicks. He could possibly also be considered a Pint-Sized Powerhouse as he was much shorter than most 400 pounders at only 5'9".
"Playboy" Buddy Rose was fat, yet he could do one-armed pushups and kip-ups. Part of his gimmick was that no matter how fat he got, he always claimed his weight was only 217 pounds. He described himself as "built for go, not for show."
Vic Grimes. An almost 400-pound wrestler doing corkscrew sentons is not something you see every day.
The late Umaga was quite fast on his feet for weighing 300+ pounds.
Rikishi can sure oversell a clothesline. He has also been known to fly off the top of cages.
Canadian trainer and promoter Scott D'Amore, most often connected to Impact Wrestling, isn't the slimmest man in the world but is capable of pulling off a picture-perfect moonsault. At least he could in the mid-2000s.
Calypso from Trinidad, whose finisher is a cartwheel splash she calls the Caribbean quake. She really caught on with the ICW and NWA Ring Warriors fans.
Kevin Steen (or Kevin Owens if you're a WWE fan) looks like a fat college bully yet is capable of doing somersault planchas and turnaround top rope moonsaults.
The Ur-Example of this has to be the 600-plus Haystacks Calhoun. He didn't do moonsaults or cartwheels, but in a time where every big man's gimmick was to basically stand there and let guys run into them, he chose to actually include real wrestling moves in his moveset.
Mick Foley is around the same size as Dusty Rhodes and was very fast on his feet and had no problem diving from the top rope. Unfortunately, years of abuse in brutal hardcore matches left him with so much damage to his hips and knees that he can barely move above a shuffle anymore.
Marion Armstrong of Celtic Championship Wrestling is big and beefy, and yet fully able to do cannonballs and moonsaults.
Downplayed by Mickie James who isn't necessarily fat— but she's visibly bigger in size than the usual WWE Diva. However, she does fast-paced moves like hurricanranas, diving Thesz Presses and flying forearms.
Snooki of the Jersey Shore shocked everyone when she stepped into the ring— and busted out a handspring elbow and cartwheel splash on Michelle McCool. She's a former cheerleader.
Lucha Underground has several guys who fit this mold, with some nearly able to keep up with the agile high-fliers that make up the bulk of the roster:
"The Monster" Matanza Cueto is one of the most terrifying power wrestlers ever seen on the show, but during his devastating debut he shocked everyone when he hit Chavo Guerrero Jr. with a standing moonsault/standing shooting star press combo! If you knew he's played by "Mr Athletic" Jeff Cobb then this wouldn't be so surprising.
The Mack aka Willie Mack has been described as having the look and build of Junkyard Dog but the speed and agility of Shawn Michaels. He looked like a power wrestler when he first showed up alongside his Kayfabe cousin Big Ryck (aka Ezekiel Jackson), but that impression didn't last even halfway through his first match when he displayed his surprising high-flying skills.
Marty "the Moth" Martinez (Martin Casaus) turned out to be this as a lesson to Beware the Silly Ones. Visibly stout running to fat (and admittedly with the strength to back it up), he also displayed a surprising array of agility moves such as a bicycle kick and top rope moonsault.
Because of the nature of the promotion, almost everyone is capable of, as a bare minimum, doing at least a diving splash over the top rope. A lot of big guys such as Cage and Texano are dangerously quick as well as freakishly strong. Mil Muertes is practically an aversion as a result, but even he is capable of delivering his deadly Reaper's Trident (Spear) by diving between the ropes to the outside.
Keith Lee is similar to the above mentioned Willie Mack in that he's much more agile than his build suggests, being able to use cruiserweight moves like monkey flips and standing moonsaults while also being powerful enough to lift most guys with relative ease.
NXT UK and Progress Wrestling's Dave Mastiff is as agile as he is beefy, and he's very much both, with his finisher being a cannonball senton and pretty light on his feet, too.
"The Urban-American Dream" Willie "Da Bomb" Richardson of Da Soul Touchaz is around 300 lbs. and the group's power wrestler. As his nickname should indicate, he is an Legacy Character of "The American Dream" Dusty Rhodes himself.
Michael "Roadkill" DePoli was nearly 300lbs but often displayed impressive agility by going off the top turnbuckle and sometimes even jumping off the ropes.
Another ECW alum Balls Mahoney was a chubby and pretty out of shape looking guy, but he could move quickly and could perform a frogsplash almost as well as Eddie Guerrero.
. He has also been known to fly off the top of cages.