Using the PowerGUI, you can list all snapshots, but unfortunately, it doesn’t list the parent VM.

I wrote a quick little function to search all VMs that have snapshots and list them.

function get-snaps{
    $vms = get-vm | sort name
    $vmsnaps = @()
    foreach($vm in $vms){
    	$snap = Get-Snapshot $vm
    	if($snap){
		  $vmsnaps += $vm
		  write-host -fore green `n `t $vm
		  $snapshots = Get-Snapshot $vm
		  foreach ($snapshot in $snapshots){
			write-host "name: " $snapshot.name " size: " ([math]::Round($snapshot.sizemb/1024,2))
    		}
    	}
    }
}
 
get-snaps

Just save that into a .ps1 file and run it. Make sure you’re connected to a vCenter or it won’t work.

Expected output is like this:
Server1
name: Description size: 0.08

Server2
name: Description size: 3.79

Server3
name: Consolidate Helper- 0 size: 1.66

Server4
name: Consolidate Helper- 0 size: 73.45

Server5
name: Consolidate Helper- 0 size: 53.61

Server6
name: asdf size: 0.02