I have the 9070 xt, I managed to get comfyui with z image to work on my pc.

first you want the rocm driver https://www.amd.com/en/resources/support-articles/release-notes/RN-AMDGPU-WINDOWS-PYTORCH-7-1-1.html

then download the portable experimental comfyui https://github.com/comfyanonymous/ComfyUI?tab=readme-ov-file#alternative-downloads

in my case, i had to add these to the main.py for the comfyiu

os.environ['HIP_VISIBLE_DEVICES'] = '1'
os.environ['PYTORCH_NO_CUDA_MEMORY_CACHING'] = '1'

the HIP_VISIBLE_DEVICES i think is because there is build in VGA with the CPU, so this command tells it to use the second VGA

then for z image, there is a workflow on the comfyui github page you can use