Expecting a second sequel when we had to wait a decade for a first sequel strikes me as rather silly. We can be happy that BG&E2 appears to be finally a thing that exists - and let's be honest, Ubisoft would have had every reason in the world to just cancel the project once and for all eons ago. It's a sequel to a game that bombed so hard it was given away in cereal boxes, after all. It's baffling Ubisoft kinda kept working on the project to begin with.
How much of a budget this will have really depends on how much Nintendo is willing to pay as well, so I wouldn't really come to any conclusions just yet. No one should expect a proper AAA game for the aforementioned reasons, though.