GMS2 Resource Importer lets you transfer multiple resources of different types between GameMaker Studio 2 projects in one go. You can import resources from normal .yyp projects and .yyz exported project archives. It's even possibly to transfer resources from some broken projects.
You can also use the tool to import external sprites and sounds. This is especially helpful when wanting to replace multiple sprites or sounds in a project. You can import multiple sprites or sounds in one go, sprites or sounds already in the project will be replaced (if you want), settings (bounding boxes etc.) for existing resources will stay the same. Read more about this in the provided documentation.
From version 0.91, the tool should work using Mono on Mac OS X and Linux. Let me know if you have any problems!