In the official editor under staff details, there is a check box for female. I assume this is their so that news using female pronouns for any female characters in the game (I think there is a Tottenham doctor, maybe more). Can you actually check this box if you create new staff? I haven't seemed to be able to.
Oh, and something I've always wondered. If you set a teams home city to be different than the nation they are playing in (ex. Cardiff (Wales) in England), what nationality will a foreign player receive after playing there for years, English or Welsh?