I found this the easiest to beat her if some are having trouble.
1. Constantly dodge her go crazy pressing that
2. When she goes up in the air, try aim for her with your SMG. You just need to hit her once and you should counter her, leaving her stunned for you to do damage. Make sure to do as many crackshots to deal more damage by pressing
3. When your tech skill goes all the way up to 3 bars. Use trigger- happy close range.
4. Video included bellow as well so you can see. Also unlike me you can keep shooting her with your pistol to keep doing damage as you dodge.