I was able to solve the problem.
Instead of using asset.get_ui_image() and pass it on to SpriteNode(Texture(..ui_image..)) I got a PIL image directly with asset.get_image() and transformed it with the scripts found here to and ui image.
relevant from above link:
# pil <=> ui def pil2ui(imgIn): with io.BytesIO() as bIO: imgIn.save(bIO, 'PNG') imgOut = ui.Image.from_data(bIO.getvalue()) del bIO return imgOut
I hope you find this useful google hero from the future. This solves “weird false inverted colors for PNG ui.image from assets in photo module”.