A few mote details about file level cloinig, File level cloning can be triggered by several factors: changing cluster size, 4KN sectors on the source, shrinking NTFS volumes or resizing FAT volumes.
In this case it has been triggered by shrinking
2019-09-26T17:43:19.526+08:00 info vmware-converter-agent[06156] [Originator@6876 sub=task-1] GetVolumeCloneMgr: filesystem type: NTFS, source sector size: 512, target sector size: 512, source volume cluster size: 4096, target volume cluster size: 4096, source volume capacity: 2146592358400 bytes, target volume capacity: 161768013824 bytes, resize requested: true.
2019-09-26T17:43:19.526+08:00 info vmware-converter-agent[06156] [Originator@6876 sub=task-1] GetVolumeCloneMgr: File level cloning has been selected for volume \WindowsBitmapDriverVolumeId=[D6-67-A3-C0-00-00-10-35-0C-00-00-00]
2019-09-26T17:43:19.526+08:00 info vmware-converter-agent[06728] [Originator@6876 sub=ThreadPool] Thread enlisted