Keep the same face across renders

Give the character an identity sheet (the last step of the creation dialog, or "Generate identity sheet" on their page) from consistent photos — same hair length, same art style. A sheet made from a short-haired photo and a long-haired one makes the engine pick one per render.

Describe the wardrobe in the prompt every time. Identity (face, build, skin tone) holds more strongly than clothing, which follows the words.

Pick an engine that reads reference pictures: the model page and the picker say how many each one takes. Veo 3.1 Lite, Hailuo 3 Max, Runway Gen-4.5 and Grok Imagine work from text alone, and so do eroq's Motion engines in Video. In Replace, Replace Pro casts your characters from their identity sheets, each in the outfit you pick.

For near-identical variations, use a seed on an engine that honours one, and change a single thing between renders.