Flux.2 Klein_Multi_Head_Swap

Multiple Head Swap Flux.2-Klein V1

This workflow is intended for head swaps involving fictional characters; it is a tool, so I am not responsible for how you use it.

It allows you to perform up to three simultaneous head swaps—provided the prompt is set up correctly—but if you are unable to complete all the necessary head swaps in a single session, you can simply reload the image and continue.

Models

I normally use flux.2-klein-9b-fp8.safetensors but if you use a gguf model change the model loader and connect it.

Recommended Loras download:

• BSF – Best Face Swap page link:
  https://huggingface.co/Alissonerdx/BFS-Best-Face-Swap/tree/main
  or direct downloading link: https://huggingface.co/Alissonerdx/BFS-Best-Face-Swap/resolve/main/bfs_head_v1_flux-klein_9b_step3500_rank128.safetensors?download=true

• Realism Slider V2: https://civitai.com/models/2401004/realism-slider

• Ultra Real v4: https://civitai.com/models/2462105/ultrareal-krea2-klein9b?modelVersionId=2846977
  

The workflow should work with qwen image edit also, provided you have the right model, clip, vae and the correct bfs lora from the same huggingface page, you’ll probably have to change the load model node with a gguf one.

Please forgive me, I've forgotten one important thing: when you upload the base image containing the heads you want to change, you have to right-click on it and choose "Open in MaskEditor", then draw the mask over the face/faces and if needed over the skin you want matching color and tone. I've just updated the markdown notes inside :-)

Tips and tricks: this workflow provides three simultaneous head swaps. Theoretically we can add some more, but at a certain point you’ll encounter tecnical limits with the model, how many token he can handles without mixing facial features and so on, AND order matters: Always list your head replacements from left to right across the image. So it’s better after three headswap load again the last image generated, apply the next masks on the characters you have to swap, adjust the prompt and generate.

Note: if the heads of the base image are too close or touching, the mixing of somatic traits is guaranteed even when performing a single swap at a time.

If the head to be modified is in partial shadow relative to the body—such as in chiaroscuro images—it is advisable to also mask the hands, arms, or other body parts that the model will use as a reference for the face's skin color and tones, without needing to alter the prompt. I'll update the markdown notes soon.

Inside you will find markdown notes with tip and tricks, including color and tone matching of the skin.
In the provided images you can see the ones with and without color and tone skin of the arms and hands.

I'm sorry, but I don't have the experience to adapt it for use with graphics cards that have low VRAM; I have a card with 16 GB of VRAM and 32 GB of system RAM. If someone wants to modify it, that would be great!

Behave yourselves and don't break anything :-)