Pokémon Infinite Fusion is really good. It’s Kanto but you can splice Pokémon together for fun and/or advantage, combining their types and movesets, and a ton of the possible combos have custom sprites. (The ones that don’t have custom sprites use old auto-generated sprites, which are at least usually funny.)
There are about 500 canonical 'mons, which means over 200,000 fusions!
Don’t trust Google, people are making fake download sites. Get the game from the Discord.
(Yes, Discord is a terrible place to keep the canonical download links. No, I don’t know why it’s like that. Yes, this whole thing was made in RPG Maker, somehow!)
2077 basically breaks from its source material over this. There’s a series of side quests where you are asked to non-lethally subdue people suffering from “cyberpsychosis” in order to facilitate independent research on rehabilitation, and it turns out that basically all of them are either a) suffering from medical side effects that (according to some other in-game documents) are known to cyberware manufacturers, but being swept under the rug to keep sales and profits flowing, and/or b) suffering from untreated psychological trauma, and it just turns out lashing out is a lot more destructive when you happen to have a ton of built in weapon systems that are always with you and ready to engage at a moment’s notice. The “humanness” angle is sometimes seen being pushed by the media, but it’s basically an excuse the corps use to shift blame away from their faulty products.