Trace Image to Grease pencil to make auto cut outs using meshes

I am looking for a way doing automated cut outs using the “Trace Image to Grease pencil”.
I wonder why it only works with an image wich is represented in the viewport via an empty.

Is there a way to use an mesh image (eg imported via image to plane) and then use the algorithm to do the cut outs while keeping the uvs?
I need to use real mesh cut outs because of bad performance when using alpha masks.

Imagin you have your unwrap and cut it out rough with the knife and then run the trace algorithm for precise cutouts.

Ok, the image foreground needs more contrast as in my video example…