There’s probably a Wookiepedia page for this, but the implication I am taking from this is that the Tuskens in general or this tribe in specific is matriarchical.
Possible, but she’s not playing the tribe chieftain. Though since they all wear the same masks it’s hard to tell if the chief isn’t also a woman, though the costume is more typical male Tusken like we’ve seen before.
My interpretation is that she’s the Tusken equivalent of a Shield-maiden, i.e. a warrior woman, whereas the females we saw in AOTC are wearing more domestic garments and masks. Alternatively this could simply be an all-warrior tribe and therefore everyone, regardless of sex, wears the same masks with only subtle variations to their garments according to individual and/or status.