Level-5 has announced during its Anime Expo 2019 panel that Yo-kai Watch 4 will be coming West for Nintendo Switch. A release window was not announced.
During the panel, a Japanese trailer with English subtitles was shown. There’s no info if this trailer will be available online later.
Additionally, Level-5 noted that Yo-kai Watch 4 has content that requires players to have watched specific non-localized Yo-kai Watch films to fully understand the game. Level-5 can’t confirm anything about bringing these movies over but they expressed their interest in doing so.
Yo-kai Watch 4: We’re Looking Up at the Same Sky launched for Nintendo Switch in Japan on June 20, 2019.