Board Thread:Questions and Answers/@comment-24.99.111.181-20150102193131/@comment-28251580-20170405115259

You can only get a character of the sex you are. But there are rare types of avatars which slightly look like one of the other sex, but are not.

I'm not sure whether you could reroll, afaik you needed to create an entirely new account for a different type of Avatar.