I have a few sketches and pictures of birds in my sketch book. When I want to add one to an art quilt, I trace the bird onto tracing paper with a fine tip permanent marker. This tracing is pinned to the art quilt.
I quilt through the paper using a dark thread and short stitch length, which is done by slowly moving the quilt while using a fairly rapid speed and the darning foot (or free motion foot).
The paper is then ripped off. If you use thin tracing paper, this comes off very easily.
I use Inktense pencils and a small amount of clear aloe vera gel and paint the area inside the thread. When it dries, it is permanent.
I hope you can use this technique on some of your quilts.