Megaman in MvC 1/2 as well as Power Battles and Power Fighters. Kirby technically in that Kirby fighting game on 3DS. Could argue Donkey Kong based on the fighting minigame in DK64. Same for Diddy Kong. Don't think K.Rool was playable. Link in Soul Calibur II. Obviously Terry, Ryu, and Ken. Lucario, Charizard, and Pikachu in Pokken. I think Joker was in a Persona fighting game? Cloud in Ehrgeiz and Dissidia. All I could think of off the top of my head.