If you are looking for a way to make sure you can run a GPO or PS script against a computer, I think you need to first determine if Powershell is even installed and which version it is. This can be done via the registry HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\PowerShell\1\PowerShellEngine for ver 1 or 2, and HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\PowerShell\3\PowerShellEngine for ver 3 or 4…under the PowerShellVersion value. Is that what you are after?
The Powershell variable: $PSVersionTable.PSVersion holds info regarding the WMF as well.