Wow, this has been a great exchange. What a wealth of experience and information.
Transparency is my main need as with other pp projects I struggled with getting the fabric where I wanted it and then once under the needle I was lifting the edges trying to see if it was still where I wanted it.
Since it is a big project I want the paper ready for the printer without cutting and I know I don't want to be tracing 64, 12 inch squares. The pattern is the Storm at Sea edged by Snail Trail.
I'm going to try the tracing paper as it is transparent but more affordable than vellum. But if it doesn't go through the printer well, then I will try a light weight transparent typing/printer paper.
I recently watch a Youtube tutorial on freezer paper but it would require cutting out the pieces. For applique I would definately use it.
Thanks for all your help!