In PowerShell we can use Get-GPRegistryValue cmled to identify the registry key(s) associated with:
More information about Get-GPRegistryValue can be found on this link:
For Enabled we get:
Specifies whether the DNS client should convert internationalized domain names (IDNs) to the Nameprep form, a canonical Unicode representation of the string.
If this policy setting is enabled, IDNs are converted to the Nameprep form.
If this policy setting is disabled, or if this policy setting is not configured, IDNs are not converted to the Nameprep form.
At least Windows Server 2012, Windows 8 or Windows RT
For Disabled we get: