Converting Thick vmdk to thin after Move from Datastore
Solution 1:
It is possible to convert thick to thin only by copying VMDK file to different datastore/folder or within the folder with proper cmdlet:
vmkfstools -i "/vmfs/volumes/<source datastore>/<vm-folder>/test.vmdk" "/vmfs/volumes/<destination datastore>/<dest-folder>/test.vmdk" -d thin -a lsilogic
more info - https://communities.vmware.com/thread/486311