I think it's going to be a new IP.
I don't think they'll do another Metroid game again, they're done with that. New IP or a Star Fox reboot. No chance one of the cancelled games gets revived, they were cancelled for a reason. It won't be Donkey Kong either, the framework for such a game has been made, no need for a studio such as Retro to do the sequel when you can have some other do it just fine. F-Zero would be a waste, because it would be too simple of a type of game and low-profile.







