According to 2ch sleuths, the name of the game is apparently Crystal Conquest based on this domain name page. The tagline in the teaser trailer is "'C' is coming."
In that teaser trailer, there are helmets, armor, and spinning crystals. Yep! It looks like a Japanese role-playing game. Wonder if it's a Japan-only smartphone title...
スクウェア・エニックスだからこそ〇〇〇がここまできた！ [Square Enix]