Level-5 has since followed up with a teaser site, accessible here.
Just like many of the recent Yo-kai Watch games, Yo-kai Watch Busters 2 is a 3DS title. It will not be a Switch game.
(=^・ω・^=) Kuroneko S2 - Ore no Imouto - Steam, MyAnimeList and Twitter - PSN: Gustavo_Valim - Switch FC: 6390-8693-0129 (=^・ω・^=)