I used the site Dream by Wombo for these pics.
https://dream.ai/createI just used the free option, not the premium. The free option only makes one pic at a time, but there are quite a few styles (scroll down to see all the available styles) to pick from.
Just type in whatever text prompts you want, ie. "two girls fighting", then pick an art style and hit the create button.
You can try to get more specific for word prompts like "redheads, long hair, hair pulling, mermaids, androids etc."
Oh, if the pic wont show due to a NSFW warning, just try the create button again. Sometimes some of the word prompts triggers that to happen randomly.
There are other AI Art sites too like NightCafe creator that are free.
But, I guess the main one people tend to use is called "Stable Diffusion".
It looks complicated and I haven't really looked into it yet. However, the art people are making with it looks really good.