If EROFS fsmerge is disabled and no fsmeta can be used to mount a single filesystem in the guest, an alternative method is to generate a valid GPT partition table instead and use VMDK to concatenate the GPT metadata + each layers into one single block device.
In that way, we need to mount each partition in the guest and use overlayfs to merge them: it can also support 127 layers if no fsmeta is available.
If EROFS fsmerge is disabled and no fsmeta can be used to mount a single filesystem in the guest, an alternative method is to generate a valid GPT partition table instead and use VMDK to concatenate the GPT metadata + each layers into one single block device.
In that way, we need to mount each partition in the guest and use overlayfs to merge them: it can also support 127 layers if no fsmeta is available.