I just recently did Co-op All Star mode, and i actually received trophies of both the characters. (which were Wolf and Yoshi incase anyone wanted to know)
This is a little harder though because if even one of you die you have to use a continue.
I'm not sure if this counts towards the 'Clear All Star with every character' challenge because there's no score or clear icon when you select the character on All-Star if you cleared co-op with him, as the score only goes toward the co-op score... obviously.
It is an easy way to get all the FS Trophies, and closer to breaking the 'Get all characters FS trophies' challenge window completed, though, if you have a competent friend.
Sorry if this is old.
This is a little harder though because if even one of you die you have to use a continue.
I'm not sure if this counts towards the 'Clear All Star with every character' challenge because there's no score or clear icon when you select the character on All-Star if you cleared co-op with him, as the score only goes toward the co-op score... obviously.
It is an easy way to get all the FS Trophies, and closer to breaking the 'Get all characters FS trophies' challenge window completed, though, if you have a competent friend.
Sorry if this is old.