I’d have a Zelda fighting game, maybe a 3D one like Pokken, but a 2D one would be just as cool.
1) Link (styled like Ocarina, and using items from that game)
2) Zelda (in pink dress like Ultimate)
3) Ganon (based on the original boar-like appearance)
4) Link of the Past (based on and using items from Link to the Past, like the boomerang, fire and ice rods, and hammer)
5) Sheik
6) Ganondorf
7) Masked Link (using items from Majora’s Mask, being able to change between the four forms)
8) Tingle
9) Skull Kid
10) Toon Link (using items from Wind Waker, like the Deku Leaf and Skull Hammer, and maybe also some from Phantom Hourglass)
11) Tetra
12) Toon Ganon (based on and using his two swords from Wind Waker)
13) Vaati
14) Twilight Link and Midna (being able to switch between Wolf Link with Midna riding, and human form using items from Twilight Princess like the spinner and ball & chain)
15) Zant
16) Link of the Sky (using items from Skyward Sword, like the gust bellows, whip, and beetle)
17) Ghirahim
18) Groose
19) Champion Link (using abilities from BotW, like the tunes and the four Champion powers)
20) Impa (based on her appearance in BotW, and playing like the Moz Koshia boss fight)
No guest characters really. I’m not even sure what series they could be from.