With the systems for both Pathfinder and Starfinder being open source, anyone out there is able to make content for them. It can be hard to keep up with all of them, so Paizo has started collecting them together in one place. Here's a look at the latest releases compatible with them.
From the post:
Check out the new Pathfinder- and Starfinder-compatible products—all PDFs—recently posted on paizo.com in the last month of 2020.