Theres an easier way to do this without changing any binds just span Square and triangle on ps4 then go in when your screen flashes pick the character you want the emote to work on then when you get out select any char with a built in emote
@@Marshynite for me I can't use the built-in emotes for Spider-Man, and Mizuki, but I can only use Wonder Woman's built-in emote since it is my only skin with a built-in emote from the item shop.