I can only convert to MOV in the Win version, and Premiere can't read the audio codec.
Hello @tvebak1970. If you are using the GoPro Max Exporter which is downloaded from this link, you should be able to get equirectangular .MOV file, then edit the MOV file with the plugin here.
See the detailed guide to rendering videos using the Windows exporter and the Reframe plugin and check the results. Hope this helps!