FFVI Chess:
White:
King- Edgar (He's already a king!)
Queen- Terra
Left Bishop- Locke
Right Bishop- Celes
Left Knight- Setzer
Right Knight- Cyan
Left Castle- Sabin
Right Castle- Gau
Pawns- Espers

Black:
King- Kefka
Queen- Emperor Gestahl
Left Bishop- Ultros
Right Bishop- Chupon
Left Knight- Biggs
Right Knight- Wedge
Left Castle- Atma Weapon
Right Castle- Kefka's Tower
Pawns- People of Zozo and their mayor Imperial Magiteks.

Too many hero.

FFXII Chess:
(SPOILER)White:
King: Larsa
Queen: Ashe
Left Bishop: Fran
Right Bishop: Penelo
Left Knight: Balthier
Right Knight: Vaan
Left Rook: Vossler
Right Rook: Basch
Pawns: Dalmascan Soldiers

Black:
King: Vayne
Queen: Venat
Left Bishop: Judge Drace
Right Bishop: Judge Zargabath
Left Knight: Judge Ghis
Right Knight: Judge Berga
Left Rook: Judge Gabranth
Right Rook: Doctor Cid
Pawns: Imperial Swordsman