I didn't mean "humanoid" as in "C3PO sitting across from the player at a table", I meant humanoid thought processes.

As far as I know, none of the chess engines are humanoid in the way they determine the next best move.

For one, they are all using far, far more instant-recall capacity than any human, ever.

> its rules don't require human bodies the way field sports do.

Which rule in football, tennis, american football, baseball, basketball or hockey requires humanoid players?

They may preclude robots as players, but that's a post-hoc fallacy - "they require all players to be humans, so therefore robots cannot replace humans like in Chess".