Kou Dai Bao Shi: Hong

Despite the name literally translating to Pocket Gem: Red, this is actually an unofficial backport of Pokemon Ruby.

This game is a hack of Nanjing's earlier RPG Kou Dai Bao Shi: Lan made to look like Pokemon Ruby. Its title screen features a Groudon, which is the new wild Pokemon trainer. Aside from renaming the character to "Mary" (玛丽), it also replaces Brendan's front and back sprites with May, but doesn't replace the rival's sprites, making it possible to face a doppleganger battle. It also keeps Brendan's overworld sprites intact.