In the game you can play as Nate, Katie, Natsume (Nate and Katie's daughter who earlier appeared in Yo-kai Watch: Shadowside), and Shin (who appeared earlier in Yo-kai Watch: Forever Friends) in three different eras. There are also stated to be other characters that can be played as.
Yo-Kai Watch 4 contains various differences from the previous games. It features an improved battle system where humans can fight alongside yo-kai and several new Tribes, amongst other changes.
Yo-Kai Watch 4 provides examples of:
- Art Evolution: The game features less stylized, more realistically proportioned character designs for humans.
- The Bus Came Back: After getting shafted in the third game, Katie returns as a fully playable character, albeit not as an alternative to Nate like in the first two games.
- Costume Evolution: Nate has switched out of his previous red jacket with an orange version of his original shirt underneath it. Now he wears an open red shirt that has a white star on its sleeve, a blue undershirt, and brown sneakers.
- Feelies: The Japanese release of the game comes with two Arks that can be used to unlock the Triple Nyan Claw.
- Opposites Attract: Ray O'Light (an energetic sun yo-kai) and Dridzelda (a gloomy rain yo-kai) had a daughter together.
- Serial Escalation: The game is a grand journey that goes beyond the time and space of the world the protagonists live in. It features three different eras as well (1950s, 2010s, and 2040s).
- Spiritual Successor: With Ni no Kuni II: Revenant Kingdom. Due to switching to a pure Action RPG approach, this game will likely be the closest Ni No Kuni 1 sequel fans will get due to its combat system, given what little of the gameplay has been seen so far.