Stepdaughter is mean

I (44f) have a 14 yr old stepdaughter who is incredibly bright (and knows it). She is in advanced math class in high school and is very social and involved in school activities - a parent’s dream on that side of things. But she dresses like she’s possessed by demons - the emo goth stuff (which I can’t stand) and wears slutty black lingerie looking clothes to school dances, which her bio mom loves because she was also a goth chick in high school (and still is to an extent in her near-40s). More importantly, she’s abusive.

I’ve been married to her dad for a year and during that time have been diagnosed with cancer. I’m a pretty spiritual person and like to speak life and positivity into everything which has been important to my recovery - and as you can guess by the title, that’s not this little girl’s fave. When she first moved in, she held my baseball bat over my head acting like she was going to hit me - I had to tell her to stop like 5 times and start yelling before she put it down (acted like she was just playing but that shit wasn’t funny). That was the worst of it - she hasn’t threatened since. Now it’s all verbal. She would share TikTok’s but they were all horrible brain rot about blood and murder and negativity or about some video game of anime school girls killing each other or some other garbage that was utterly meaningless. She snaps at me and starts yelling that I’m “yapping” if she doesn’t want to hear what I have to say. Then the other day her friend came over and my husband said something about I look pretty while bald (from chemo) and this child said I “look cooked” which I now learned doesn’t mean anything good. Her friend was sitting next to her and even looked at her like she’s a jerk (because she is).

Long story short this kid needs an exorcism and I tried to play nice but now I’m going into mom mode and want to help this kid turn around. I’ve seen moments where she is capable of being sweet (though they are few) so I know she has it in her. Her grandmother brought up her behavior before I did and completely agrees with me. I told her dad about all this stuff but he doesn’t correct her because she is mean to him too and he doesn’t want to deal with it, but I’m genuinely concerned she’s going to grow up to be a sociopath. Anyone can ChatGPT their way thru some math class these days - if she’s a jerk as an adult, that’s a way bigger deal. I asked him to get her on a chore routine (because she doesn’t help with shit of course unless coerced) and that we need to do more activities off the internet where she constantly absorbs all kinds of negative trash. Now my husband tells me I “have it out” for her which is not true. I want his support cuz she isn’t my child. He won’t really help but won’t stop me from trying either. I’m genuinely worried this kid is going to be a garbage adult and society is gonna have to deal with her being unemployable because no one wants to deal with her after high school. Also hoping to give her some exposure to spiritual health and how beneficial it is in hopes someday she chooses spirituality over acting like a vampire (like her bio mom still does today) and spend more time being happy instead of devising ways to make other people unhappy.

TDLR: Stepdaughter is a jerk. I want to implement more rules in the house to help curb her negative behavior but my husband just thinks I just have it out for his daughter and want to make her miserable but doesn’t stop me from trying. I truly just want to try to teach this kid how to be a better human. Also share spiritual beliefs that her parents don’t share but why can’t she get the right to at least see for herself? Advice on how to work around this dynamic and help her as her stepmom?