My initial thought on what the Switch game would be (before the trailer) was "Warioware with "plot" ". Maybe I was on to something, since both the SK Switch trailer and Warioware have this:
..Or not. Now I can see where the visual novel idea comes from, but it could also still be a 2D Beat em up, just with the story sections told in first person perspective & heavily interactive (to take advantage of the joyconz). That'd explain the Asuka screenshot, since it seems like she's holding the player's hand.
Still, I wouldn't write off the game being a spin-off, since it is called "Shinobi Refresh", which might hint at a more laid back title.
Also, my personal ranking of the Senrans (only counting the ones in EV):
32) Ryona
31) Oldbag Sayuri
30) Hanzo-Asuka
*skip*
5) Hanabi (even though she plays the worst.)
4) Homura
3) Yomi
3) Katsuragi (tied because I really can't decide)
1) Big Ryona.