Ah welcome! First official person in this thread that isn't just me lol.
Anyways, what you're referring to would be PSA's from the Brawl modding scene that let characters have their own custom movesets and character slots. Here's some examples of early Touhou PSA's from Brawl.
https://www.youtube.com/watch?v=ZmFKxKcHqWw&list=PLnYJ_NXfiZOjecCbbXK95hGebzdY-dDK0For Ultimate, it's 100% possible. In fact, people have made lots of custom moves already. The problem is that whenever Ultimate gets updated, all the custom move mods break, so they have to be re-coded again from scratch. An example is this one which gives every character Falcon's knee, which while it works for now, will definitely break come next patch.
https://gamebanana.com/gamefiles/12894So while it is possible, we're stuck waiting until Ultimate finishes it's updates. Extra character slots are possible, but not added for the same reason.
The biggest advantage that Ultimate has over the modding scenes of other Smash games is that there's no file size limits. Which I can't understate how insanely good that is. Even Brawl; what's commonly seen as the peak of Smash modding, has file size limits, which limits custom movesets. But in Ultimate, there's literally none. Here's a thread that goes over it in more detail. It's a bit outdated, since even more discoveries have been made, but you'll get the general idea.
https://gamebanana.com/threads/218129If you're particularly observant, you'll notice the thread above was posted 4 months ago, in August, when I first started modding Smash Ultimate and started this thread. This is no coincidence. In fact, I've been wanting to mod Smash for a long time, but never saw any reason to mod any of the newer games over Brawl. But ever since that discovery 4 months ago, I can safely say that Ultimate will have the craziest custom movesets possible due to their being absolutely no file size limits. And I fully intend to add custom movesets for all the Touhou model swaps once Ultimate has finished updating.
So right now, I'm just working on aesthetics. Getting the graphics out of the way so I can focus on customization later. In fact, here's some progress I've done just yesterday.
https://www.youtube.com/watch?v=TN2lx0fHLV4I've also put all the mods into one download link. So it's like this modpack's first official release in a way.
https://drive.google.com/file/d/1BSjz9Em5Pf4sQTdIAV-lZ5ernVryxWfThttps://gamebanana.com/projects/35608
