https://www.openstreetmap.org/node/10121264065
https://wiki.openstreetmap.org/wiki/Tag:sport%3Dchess
How to map
Since this is a non-physical tag, it should always be combined with some appropriate (physical) tag. For example:

With leisure=pitch when tagging big chess-boards in the open air
With amenity=table when tagging public chess-playing tables
Some users have added leisure=picnic_table to tag public chess-playing tables, however this is inconsistent since the table is not used for picnics (see discussion page)