Hi there. I'm looking for where to find FBX Exporter that's described here: https://docs.unity3d.com/Packages/com.unity.formats.fbx@4.0/manual/index.html . It doesn't seem to show up in Unity 2020 package Manager
FBX Exporter is still in preview. You need to enable preview packages in order to see it. Alternatively, you can click on the +, then "Add package form git URL…" and paste in the package identifier "com.unity.formats.fbx".