Not to much already, but in a nutshell batgirl users that i found use very few low attacks, if not any, as she has only one low starter.
All her special attacks hits high/mid/overhead, except the follow up of bat-cartheel(Bat rueda in spanish, don't know if it's that translation), wich starts in an overhead and follows with low or high, so if you see it just crouch the follow-up hit.
Her teleport it's very unsafe, you can punish her with almost anything, but ihas a really quick start up, so if you are in the air she will catch you, so jumping against her it's not advised.
Her batarang hits high, so you can crouch-advance it without problem, but her batarang that shackles you hits mid, so keep that in mind. Also their recovery time it's pretty high, so you can charge on reaction. The only con it's that the second one can be dash canceled, but it's pretty rare to see that.
Many batgirl that I have see tries to jump against me, eating armored venom uppercut for free.
I have much to test yet, but that's my first impression of her