If you're looking for a service to create comic art from text prompts and reference images, ComicsMaker.ai is a good all-purpose option. It's got a collection of AI tools, including Text to Image, Image to Image and ControlNet tools, that can convert your prompts and references into comic art. It's available on a variety of pricing plans, and you can use it for commercial purposes under the Creative ML OpenRAIL-M license.
Another good option is AI Comic Factory. The service, which uses Hugging Face Space, lets you create comic books with AI, with several comic styles, layout choices and the ability to upload your own images for more control. It'll also keep character designs consistent from one page to another. Pricing ranges from free to premium levels, so it's good for casual and serious users.
If you want photorealistic comics, Neural Canvas is a good option. It lets you create comics in a variety of styles and moods with more than 100 characters. The service is easy to use, and a single payment will get you a 25-illustration comic book, so it's good for beginners and more experienced artists.
Last, Dashtoon Studio is a relatively easy-to-use service that's designed to deliver consistency and control in turning a story into a comic. It's got tools for creating your own characters, different style options and AI tools to turn a storyboard into a comic. Dashtoon also lets you publish and monetize your comics, so it's good for new and experienced creators.