Watching it on the Treehouse Live, it looks like a lot of fun. The character designs are different for Nintendo but more modern and a nice balance between being kid friendly but not so much that it isn't fun for older folkes too.
I don't want to go crazy and say it's the next Splatoon, but it looks like it could become a solid new IP for Nintendo.
Looks a Powerstone meets Punch-Out meets Street Fighter IV hybrid. Character designs are reminscent of Overwatch too, which I immediately looked at thought Nintendo needed a character IP like that. Also you can play with regular buttons/joypad too if you don't want to use motion controls so I like that like Splatoon they give people a choice.
Here's the Treehouse footage of the game being played by the Treehouse staff:
https://youtu.be/qadzCB3CLlI?t=44m16s
