It would be the biggest disaster you could imagine, Final Fantasy 16 would take 16 years to get finished and I would be fired 4 years into making it because it took them 4 years too late to realize their mistake.
But if this ever happened I'll just hire Sakurai and say he can have access to any of the Square Enix characters in smash if he+Nomura would be the "executive producers" on this with them doing 99.99% of the heavy lifting.
Actually you know what, NEW PREMISE. Halfway into development the entire project is a mess and I'm about to be fired because oh god why are Cloud's skin textures actual cloud textures. Suddenly, a new idea comes into my head "Super Sma-" never-mind taken.... "Boxing" because it'a squar-....yeah no. Phoenix Square off, because that's the best I can do at naming a fighting game.
You hated the fire emblem characters in smash? Well get ready for 75+ Swordman with wild ass anime hair that keeps the game from being 60+fps because I insisted on hair physics.
Coming in like 2034 because 16 years of development and oh god how did we spend 400 million on this....oh right yeah that Giraffe concept art vacation.