I don't think it'd be that great. I don't see why people are so in love with the Fierce Diety or "Oni Link". Yeah it was really fun playing as him but it was only something extra they put in the game for the people that collected all the masks. He wasn't meant to be this great popular mysterious character.

I just say no we don't need the Fierce Diety in any other games. Plus what would it even be about (besides the obvious)? Just seriously I don't see how they could create an epic game out of it. Lastly they need to be focussing on actual Zelda games that contribute to the overall story/theme to it other than all these little side games people keep hoping for.