C64 Chess Project (C64hess) by Chessforeva (2015) is a chess puzzle game where you try to achieve checkmate in 1, 2 or 3 moves.

Chess Champion for the Commodore 64 was published by Green Valley Publishing.  This is a pretty entry level Chess game with 7 levels of play.

Colossus Chess 4 written by Martin P. Briant, published by CDS Software in 1985 - From what I've read in reviews, this is one of the strongest chess games you'll find for the Commodore 64.

Modem Chess v2.0 by Bobby Smith and Mike Quinn is a classic chess game for the Commodore 64.  Contrary to its name, it doesn't require a modem, or even have the ability to use a modem.