I am with Spirit. Zelda Calibur would be a better choice. Smash's focus isn't really on the fighting itselfi although people do play competitively the game is more of a casual experience and fanservice to try to please all Nintendo fans. Smash Ultimate already has lots of Zelda stuff in and they'd just be better off adding more Zelda characters to the existing roster than making a whole game of Smash Zelda edition which might feel like an emptier super smash bros.
If Zelda were to be a fighting game it should be based on Soul Calibur which is a weapon based fighting series. The focus is on the actual fighting rather than random stage events and I just think it would be more suitable to make one with a Zelda cast and Zelda stages.
Not enough fighting characters to make a fighting game. You got your Triforce weilding characters, all with multiple iterations, then you got some other characters with notable fighting abilities like the champions from BoTW. But what would all of the other characters be? Bosses? Come to think of it, maybe it would be cool to play as like Bongo Bongo and just bash the **** out of other bosses that previously gave you a hard time... that alone could be a stress relief game.
Other than that idea I'll of smashing stuff as a boss, no real need or want for a Zelda fighting game. That being said, it's about time for some Zelda newcomers in Smash Bros. I'm hoping for some characters like Onox or Vaati as fighters, and maybe some non-fighting characters like the Happy Mask Salesman or Ravio as assist trophies.
I thought about this myself and thought it would be cool, one where you can play as every canon Link (currently 12 for those not keeping track) along with a bunch of different zeldas and villains from the series. But looking at these other replies I have to admit that it would probably be a better fit for a soul caliber type game.
That being said I think we really need some more Zelda representation in smash. We technically had a new character in brawl but in reality haven’t really had one since melee. My personal pick would be tetra, followed by skull kid and maybe vatii. Also if they ever remake subspace emissary I would love for them to add in some toon link levels and cutscenes. That, along with the other unlockable characters is what my only issue with it was.