1) 4 of those above are Square Enix properties.
2) Yoshida is personal friends with the Yokai Watch guy. It was more “for the lols”.
3) GARO is a famous Japanese thing that collaborates cheaply and easily with a lot of things.
4) If anything Disney related were to collab with FFXIV, it would undoubtedly be Kingdom Hearts before anything else.
5) The Nier collab was very negatively accepted, to the point they essentially shut down in game major collaborations to instead do in-game lore related raids (Pandemonium and the series related to the 12 gods).

I won’t say never, but 99% sure the avengers will not be a thing.