Based on the last 10 years of posting on here, I doubt this feature will ever be realized. But let’s give it a shot.
Similar to how many journals are providing links to references within the PDF, it would be nice to link cited references to a paper within your library. So if you are reading Paper A and you download reference 1, there could be some link between the two. This could either be a reference field listing the linked references, or a diagram linking the primary paper with branches connecting the references. I do realize the complexity this could bring about, with papers being connected to other papers. In the simplest terms, I’m trying to avoid re-downloading a reference that I already have in my library. It’s not exactly easy to search for a paper in your library while you are reading the paper within endnote.