fbx to usdz conversion is typically searched by users that are looking for software tools that can be used to convert 3D models from FBX exchange format to Universal Scene Description format package (USDZ).
This is mainly due the fact that many 3D modeling tools support USD format, but not the zipped package variant USDZ, which is a variant more dominant on macOS platform.
Your best option how to do this is to try out Blender, it's free and available for every platform, so should work for pretty much every user.
Updated: October 11, 2023