I think you'll have a very hard time turning under the edges of a flannel snowflake made from a pattern that was intended for wool (meaning no seam allowances added). There are just too many ins and outs and sharp angles. Raw edge appliqué is probably your best bet, but fusible web is not reliable on either wool or flannel due to the nap. I wish you luck with whatever route you take.

As an aside, Wonder Under can be run through an ink jet printer so patterns can be printed directly on it assuring an exact duplication of the pattern and no wasted time tracing.

Yes, Ghostrider... i've wondered about that... I will look for Wonder Under when in OKC... hmmmm, I've only bought a few FQs of the flannel with this very concern... Thank you so much for your help!!! I'll let you know what happens!!

You are so welcome and I'm excited for you!

Edited to Add - I don't think you'll have any issue turning under the flannel unless it's a very intricate snowflake. But keep in mind raw edge applique doesn't hold up as well to washing. ;)

Do the snowflakes have to be flannel as well? To me, it would make sense to do them with a more tightly woven fabric. Felted wool might also work for the flakes, allowing you to do machine buttonhole edges, or even a simple top stitch leaving the edges to fringe.

BTW, Yes, cut freezer paper works well in the copier or you can make of stack (stapled or lightly ironed where it won't hurt) and cut several at once.

I would use freezer paper and do turn under applique and then glue it down before sewing with a blanket stitch or applique stitch on your machine...