Okay, here’s what we know about the new Touhou game:
A) It’s animal-themed, in that the story blurb talks about youjuu (animal youkai), all the known playable characters other than Reimu/Marisa are youjuu, and the Japanese title is 獣王園, roughly meaning “beast king garden.” Given that Yuuma has previously been referred to as a King of Beasts and we know that the animal spirits from WBaWC are back, it’s pretty likely imo that we’ll see some of the animal yakuza again.
B) It’s a Phantasmagoria-type game, meaning head-to-head multiplayer danmaku battles like PoFV. However, the blurb also mentions that the gameplay will be closer to a standard Touhou game, and story mode might have different mechanics to make it play better as a single player game.