About Play Xiangqi
Play Xiangqi is for one game with someone you know. Open the site, send the link, play. Neither of you signs up.
Every move is checked against the rules on the server before the other board sees it, and the server runs the clocks. The same rules code runs in your browser, so the board you see and the board the server keeps cannot drift apart.
Judgements follow the 2018 World Xiangqi Rules. Two of them differ from chess and surprise people: a side with no legal move loses, and repeating a check three times loses.
One thing the rule book leaves to a referee, we leave alone: whether the remaining pieces can still force a win. We never declare that draw automatically.