So I was playing chess at ICC where I am a member. I lost the game and I usually like to offer congratulations and a handshake to the winner. So on this occasion I said handshake and she, the other player, replied, foot shake.Isn't this a strange reply or was it just a joke of some kind that I didn't fully grasp ?
Consider it being a joke and move on. There's a lot of strange people on chess servers, there's people who speaks poor English, there's people who tend to harass or offend other players for their amusement...
If you come to the chess server to play, ignore the comments from others and just play. There's no point talking to strangers, unless they offer a sound advice of some kind (that's pretty rare occasion).
Once done with the game, say "thank you" or anything you like and move on. Life's too short to spend time pondering on meaningless comments.