I showed this item to my boss who is from China.
She said the two guys playing chess are like "chess gods". Not Gods with a capital G, but higher than a normal person.
The poem was a little hard for her to translate to me, but basically it means:
The guys are having a chess "war".
They know each other well.
They don't care what is happening in the 'real world'.
They don't notice that a long, long time is passing.
She said she never saw anything like it before.
The Chinese characters are 'old style'.
It is not a money coin.