I really don't know, to be honest.
The gameplay seems to be a light beat-em-up/platformer hybrid with mini game elements. So, it is a little all over the place, seemingly.
This being Nintendo, I think maybe they just want the game to be a bit of surprise when it eventually releases. They don't want to give everything away in trailers. I feel like there's a least a handful of costumes/stages we won't see anything from until the game actually releases.
All I know for sure is...it sure looks pretty. And it's kind of piquing my interest as a bit of a Magical Girl Anime fan. Hopefully, it's good.
And a bit of a tangent: With the whole stage play motiff, the action platforming, and the focus on a bunch of different costumes, you know what it really reminds me of?
Balan Wonderworld.
Now, this is likely to be MUCH better than that game, but I have to wonder (heh) if there was some inspiration taken, here. Like they took one look at Balan and said "You know what? We could make that work. Let's show Yuji Naka how it's done!" So, I do wonder if this was a attempt of sorts to do Balan Wonderworld right. Because, I think everyone agreed there was a seed of a good idea in there. It was just the execution that fumbled everything.