I had to to migrate 43 Virtual Machines today, from one Datastore to another.
The environment is still not upgraded to vSphere yet.
Options I had:
I found the most efficient to be the following
Get-Folder "<Folder Name>" | get-vm | Move-Vm -Datastore <New_DataStoreName> -RunAsync
The plug-in was too many mouse clicks, and the command line - I have never tried - so I do not know if you can run it against multiple machines
The command completed within 3 minutes - and the storage VMotion was queued for all Virtual
Machines - it did take a bit longer
Hope you enjoyed the ride!