Ok. I'm not seeing this. Chess is not a very popular game in Japan. The game is JAPANESE! Shogi is the Japanese equivalent of chess. Shogi involves two sides battling, but usually has white, and tan sides battle. Chess is NOT played in Japan very often at all. I know that Knights and whatnot were European, but those legends are universal. Everyone knows what a knight is. Most Japanese children would not know what would be going on if there were references to chess. Like for example, if I were to ask you how you move a Gold General in Shogi, there's a 90% chance you'll go google search it. If the character were named Ote! you would have no idea about the reference. This is more likely than "checkmate".
Also, I'm not seeing the translation between black and white to good and evil to chess. Black and white are two opposite sides. Good and evil is in morality. Good and evil is a judgement, not a visible/physical trait. Chess is about two equal sides fighting. Black and white are opposite, but not EXACTLY equal. I don't know... I'm not seeing it. Just using my fail logic...