Hi,
Your Freeradius can be situated anywhere - not only local to pfSense.
It is possible that you make your own logging page that includes all the logic (probably API access) to the facebook, google, twitter family. In this case your page would be somewhat more complex as a simple html line-up.
There is no "click here and click there" and pfSense handles user identification with Facebook or Twitter.
From what I understand reading this : https://www.netgate.com/blog/netgate-integrates-pfsense-with-google-cloud-identity.html something is coming up using Google.