PS4 version of Yo-Kai Watch 4 includes new elements that will also be coming to Switch.
Yo-Kai Watch Blasters: Red Cat Corps & White Dog Squad Review (3DS)
Yo-Kai Watch 4 ++ Announced for PS4, Switch, Adds Online Co-op, New Maps and Characters
Yo-kai Watch franchise - Page - NintendObserver
YO-KAI WATCH 4 DLC ANNOUNCED! Multiplayer, New Yo-kai and More!
Yo-Kai Watch 4 (2019), Switch Game
Yo-Kai Watch 4 ++ Announced for PS4, Switch, Adds Online Co-op, New Maps and Characters
Yo-kai Watch 4: We're Looking Up at the Same Sky : Video Games
Yo-kai Watch 4++ details multiplayer mode, new quests, and more new yo-kai - Gematsu
Yo-Kai Watch 4++ on PS4 Guide : New Features, Characters, and More
Yo-Kai Watch 4 ++ Announced for PS4, Switch, Adds Online Co-op, New Maps and Characters
Yo-kai Watch 4++ Re-release/Paid Update Announced for December 5 Release, Details Inside : r/yokaiwatch
Yo-kai Watch 4++ announced for PS4 and Nintendo Switch in Japan - LootPots