He's a dryad! He looks so organic which is the complete opposite of his usual self, and that's why it works - he's still obviously different from the rest. The flowers on his waist are esp cute - I BET he can regrow them at will and sometimes hands them out as gifts!
And his leaves make a wonderful calming tea-
I guess I'm thinking way too much into this but regardless... I was a fan of the movie Epic, and Fairy!Verse makes a great AU.