I still don't follow what you mean by "trace"(I know what tracing is in art). I've been playing around extensively with AI art and already read up on it. It works by training on images it's being fed, breaking down elements on images and seeing what it can make with it. At max what has happened here might be image2image, aka put an image in and it will iterate on the image. If you put in an image like some idiot, iterate a couple times on it then it clearly is the same, I'd guess that is what you mean by tracing, right?

This was done in a non-normal way though, usually you'd start with a prompt, not with an image but I don't know where the images come from in general, maybe as a proof of concept shown what it can do but I wouldn't know. I've done something similar with my own art where I put it into the AI, still give it a somewhat similar prompt and making different versions of it, but you could still see it was somewhat mine.