Only Square and Nintendo can answer this question, if they choose to do a videogame crossing the Legend of Zelda universe with the Kingdom Hearts universe.
Kingdom hearts wouldn't exist anymore, because Link would destroy it!
Donald, Goofy and Sora would explode from Link's awesomeness
Yes they would, Link is just that awesome
Agreed, Link's powers are endless. If they did make a game like that I would probably hate it though, because they two games just. Don't. Mix.