If you're looking for a service to make anime-style art with AI, niji・journey is a great option. The AI tool lets you create anime images based on prompts you can customize, and you can also upscale results and create variations. It also offers a premium subscription with private image generation and commercial use licenses, so it's good for personal and professional projects.
Another option is Yodayo, which is geared specifically for anime fans. Yodayo has a range of tools like an AI Art Generator with stable diffusion models and guides for creating anime characters. It also has a feature-rich platform with a chat interface called Tavern, subscription plans and a system to earn YoBeans, so it's a fun place to make and discover anime-inspired content.
If you want a free, web-based option, Anime Art Studio offers 24/7 access to more than 100 stable diffusion anime models without requiring you to sign up or pay. It's got a range of tools to create images, voices, videos and animations, so it should be able to accommodate whatever you need to do.