After installing an macos vps it is possible to copy the OpenCore efi boot partition to the main macOs hd efi partition.
On my system: "sudo dd if=/dev/disk1s1 of=/dev/disk0s1" (please re-check with "sudo diskutil list").
After this, the OpenCore.qcow2 HD is not needed anymore but Quickemu does not have an option not to insert this HD to the command list. Removing the OpenCore HD makes the boot screen simpler and the default disk usually is the main disk.