stl to usdz conversion is used for the purpose of exporting STL 3D models (meshes for 3D printing) to Universal Scene Description format. Most, if not all, tools that work with USDZ format can also be used to import STL format, so you should have plenty options for this, especially on macOS platform. You can also take advantage of various 3D model converters.
Updated: September 14, 2023