out of curiosity... what is the expected size of the chess board? something that can fit on a palm of the hand or something meant for mall or park? how about space under of over it?

Normal to larger than normal size? Depends on the size of components I need to integrate in each field, the final plan is to integrate it into a larger interactive coffee table, so I’ve got some space to work with.

 

I've done a lot of work with RFID in commercial electronics I've developed for people. Your RFID has a range- normally from a few to many centimeters, so be aware of that. Secondly, you put the powered transmitter side on the board, and you put the programmable RFID tag on the bottom of the chess piece. You then write a program for your transmitter (or a special square on the chessboard) that can be used to 'program' each piece to give it an identity as you pass that piece over the transmitter and tell it what it is. Pieces have no power- are inductively coiled, as Ya'akov stated.

Instead of buying a lot of hardware, buy 2 or 3 pieces and test spacing on the board to see if you get crosstalk between spaces, and adjust spacing accordingly.

 

Certainly shortening the range of the transmit signal will require some effort. Probably producing a very directed magnetic field. The good news is that it will only need to be a very short range.
AND, I never said it would be simple.