I think if the person is white you can use “stand your ground” and shoot people of color without issue. This isn’t about her having a bat, it’s that she doesn’t look “white enough” to use the same defense several white folks have used now. And those white folks went looking for trouble and still got to shoot people with impunity. She only had a bat and was basically telling the Karen if she wants a problem to keep it up.
I just don’t see how that isn’t self defense. She also feared for her father’s life from some racist shithead that instead of calling police if she really thought there was an issue, decided to put her hands on this gentleman and then continue to harass him. And I don’t know that stores particularly policy, but most chains strongly discourage harassing and chasing down customers because you have a hunch they may have taken something. So she also likely broke store policy in pursuit of her racist vendetta.