Daily Yo-kai Watch Factsさんのイラストまとめ

Nate can be seen watching a show called "Fumetsu no Seiya" in Episode 20 of the Yo-kai Watch♪ anime. It stars a boy called Danjiro Karate, the name of the TV show and character being references to the manga/anime, "Demon Slayer".

Mangetsuotoko is the reincarnation of Ray O'Light, and instead of a sun is a full moon.

Yo-kai from the Dragon Slayer Puni Puni series are seen to commonly wield a variant of the Yo-kai Watch called the "Dragon Watch", despite also being Yo-kai themselves.

The Yo-kai Medallium states that Komashura is a "legendary Komasan with the heart of a greater demon". This implies the existence of multiple Komasans, although how one of them turns into Komashura is never further explained.

Lord Enma can be seen shooting down plushes of Jinpei, Sandayu, and Mera, who are sporting their appearance from Y School Heroes: Gag Side Stories in Chapter 8 of the Enma's Holiday manga.

Snake King Army Yo-kai from Yo-kai Watch Puni Puni's third shogi event all have the common characteristic of wearing bead necklaces.

Yo-kai Watch 4++'s opening has a texture error on Lightside Shogunyan's helmet, where its emblem is green, red, blue, purple, and black, as opposed to its usual gold.

Sgt. Burly is based off of American martial artist, Billy Blanks.

Nate's mother, Lily Adams, is seen without her signature orange tie in Yo-kai Watch 4.