AD FS on Windows Server 2016 is commonly refered to as ADFS v4.
If you need to do is send the actual user's email address as a Name ID of Email type to a relying party, you can use the following mapping:
- Extract the email address of the user as map it as the E-Mail Address claim with rule wizard Send LDAP Attributes as Claims:
- Then you can map the Name ID with a Transform an Incoming claim rule:
You can also pick another format there according to your application's requirements.
(the rules need to be in this order)
Of course, that will work only if the user actually has a mail attribute. If you want to send the userPrincipalName (UPN) as a Email Name ID type too.