Hi-ho!
Kermit THE Frog here! (The Muppets)
Kermit is one of the most iconic fictional characters in American history, and if we're only to have one acquired character Kermit would probably be the best pick since he isn't tonally out of place like most of the Fox IPs and doesn't have the potential to overload the roster like Marvel and Star Wars do.
Kermit is a movie star, and in a lot of his movies he plays different fictional characters - for this we could possibly give him a stance fighter moveset, but even if not we could do a fun movie-stunt and filming themed moveset with cameras, lights, explosions, and maybe - if we can get it to work - a stunt double. (perhaps said stunt double could even be Constantine, his evil doppelganger!)
Additionally, Kermit is famously floppy, this could give his attacks a unique movement - he'd obviously be a lightweight given his tendency to fly off when hit.