The only option found at this stage is for videos: by making full “clips” which are then transferred.
On the other hand for the photos, their edition does not allow to make a copy in the app and therefore I have not found a way to copy them for retransmission.
I also did a “save on iCloud through IOS File app. I was worried that this was not the native GoPro file but from there I managed to transfer them to GoPro cloud via the web app on a Mac. The result seems to be a priori identical to that of the clip. Paf against, here too, this does not work for the photos because the exported files seem devoid of any EXIF metadata and therefore the photos, once downloaded, appear on the date of the download instead of the date taken ….; (