Has anyone ever tried to do machine embroidery applique using a loftier fabric, such as repurposed sweaters, sherpa, fleece, etc? I'm wondering if I dare try these without a planned visit to the repair place. And if you did get it to work, please share any secrets that helped along the way.

My mother in law passed away last year. I've been going through her clothes, and found lots of buttery soft sweaters. Unfortunately, they have moth holes, so they are not good for much except in pieces. I'm working on a batch of quilts that will be going to the local children's hospital, and would like to applique sweaters and mittens, hats and such on the non-pieced blocks of my quilts. I thought a tactile applique would be a nice addition for these children.
Thank you!