Yes, also in the manual of the first Metroid game Samus was referred as a 'he', but when you beat the game you found out she was a woman. This could easily be the case here since Galacta Knight is only referred as a 'he' in one game. Plus, since Galacta Knight is pretty much Meta Knight's opposite in terms of looks would it really be crazy for Galacta to be the opposite gender as well?