I don't know who AL is and I don't really care. I can wait until Kishi reveals it.
But about the unknown member.
If I look at the Akatsuki pic in elnino19's signature, it doesn't seem like a girl to me.
But then again, I don't even know if that pic was done by Kishi or not.
But if it was, I don't think that the unknown member is a girl.
Ps: Have you read HxH. The unknown member looks just like one of the guys in the combat tower. The one in the wheelchair with two wips.
"For Feanor was made the mightiest in all parts of body and mind, in valour, in endurance, in beauty, in understanding, in skill, in strength and subtlety alike, of all the Children of Illuvatar, and a bright flame was in him"