I actually use wax over modge podge. I felt first then modge podge cause I do like it hard. Modge Podge over felt almost feels like plastic, it doesn't get really hard.
But that is comparing apples to oranges. I have never sealed a thread nose. It does sound like wax is not what is needed. It does not get a high gloss finish. It gets what would be sheen like rubbed leather I think.
Oh yes you are so right! I used it to make book marks out of fabric. In the sun the stuck to the pages of the book. It does stay a little tacky. If you sand it down though and give it a light coat of paint it takes care of that. But that also defeats the purpose if you want a shiny nose right?
I also never use it straight from the container. I dilute it with just a little water. It takes longer to build up but seems to work better.