https://civitai.com/models/711571/ben-tennyson-ben-10-2005-pdxl-lora (not mine, I take no credit)
Trained on Pony Diffusion V6 XL with 47 pictures. Best result with weight between : 0.8-1.
Basic prompts: 1boy, bentennyson, brown hair, green eyes
Outfit prompts : shirt, green cargo pants