Unless Disney release that sequel pitch about other districts (birds, fish & reptiles) colliding with Zootopia's mammals, I don't know why anyone would worry about Goofy. As for Donald, things could be interesting. But I doubt they make a big deal about it. If anything they would waste a lot of potential if they just remade the plot of the film instead of an original story. I see more freedom doing something new and fresh with the setting. But then again it would probably take them a long time to develop the world from scratch.
A Moana world would be a tad bit easier to create, especially since the water simulation already has been touched upon with 3. I'd much rather see Nemo as a underwater world, unless more time will be spent in the realm of monsters. Everything on surface in Moana would be way too repetitive.
RIP pre 1980s IPS.
Predictably enough I'm contented KH3 debunked a dragged argument in the fandom, that no IP could fit unless it was distinctly different. Well that no longer matters. Any choice of non-used Disney property could have made the story work. Yeah even Chicken Little. No longer will I be able to take someone's counterargument as an excuse (for a dislike of the named IP) as an valid point for not being considered.