Setting userPrincipleName as Okta username in an IDP flow?

I have inherited support of an Okta system in my role and I am trying to figure out how to reconfigure on of our SAML 2.0 Identity Providers so the userPrincipleName attribute is used for the Okta username. Based on the documentation it appears this would be done by changing the NameID-Format sent to Okta from Azure AD? Would we need to change anything in the attribute mapping for the IDP entry within Okta?

Additionally, how would you do this for an Active Directory integration? I looked at the documentation for this and am honestly very confused. I don’t see anywhere in the Profile Editor where you can actually set userPrincipleName as the Okta username. We have a combination of both for different environments internal/external to our environment.