Rijosroberto Well, if it’s already been booted once, then the flag saying “expand the partition on first boot” would have already been removed. So that would be correct, only a new image does the expansion to fill the remainder of the drive.
You don’t need to clone images to install Batocera to another drive. Just flash Batocera to it, boot it, and then copy your roms/saves/etc. to the new userdata partition.