>>55892233There's kind of two ways to play the joker. Either you play up the camp and make him a goofball, which is typically too silly for the pokemon setting; or you play up the anarchy and nihilism, which is too grim for the pokemon setting. The closest we have to the campy Joker is the anime's Rocket trio. I don't think we have anything close to the edgy joker in canon. Maybe... Ghestis is sort of approaching it, but he's a long way off.
Before anyone gets any big ideas about writing their own expy Joker, be forewarned that a badly written joker knockoff is one of the most unbearably cringe villains imaginable. I would advise against even trying it.