According to a tweet of Sonia Im, a Public Relations Manager of Square-Enix of North America, she’s working on “stuff” for the un-announced game. To be specific, she said that she guarantees that people will be excited when the game she’s working on is announced to the public. Since we have no idea what it is, I am guessing that it could be Kingdom Hearts 3 (unfortunately, it’s not)?
No hints were revealed. I guess all we can do is wait for the coming days or weeks before Square-Enix decides to announce this game.Square-Enix Working on Unannounced Game?,