licensing – Is using image found on google (without watermark) and turning it into pixel art with some filter would be illegal?

I’m working on AI collage generator with multiple png images from the internet (using google images search) and I wonder would my program break the law or not.
Program checks for watermark and omits images with watermarks.
The images will be pixelified like very much, even PNG image of a flower 1024×768 will be transformed into 16×16 pixelified image.

It’s like you type “barn with a sun and a horse on a field nearby” will create image with taken images from over the internet, but it will be like pixel art.

Generated images can be used by anyone, no matter the purpose.