Wow the game is just oozing with polish! I find it so hard to prioritise and implement nice transitions or effects but straight from the menu to selecting and moving pieces looks and feels great! As everyone's mentioned a really interesting concept that seems like it really changes up the meta of chess. Good work done in a short time!
p.s. isn't chess AI notoriously difficult to do? Not looked into it myself but I've always thought it was a complicated system (maybe because I don't play chess much myself '^^)