we are reworking the import code , along the new backup code ( https://xcp-ng.org/forum/topic/10664/our-future-backup-code-test-it ) to unify the differetn disk transformation path
For now:
V2V handles flat, cowd, sesparse, stream optimized vmdk in the format "metadata.vmdk and a data file ) and ova ( for VSAN)
disk import support monolithic vmdk ( cowd, sesparse, streamoptimized )
ova improt support only stream ova with streamoptimzed vmdk inside