As per my test of login through auth0 with external identity provider, in my case the Kakao, I found out that the auth0 passes user info to the Barong server with the external identity provider's information about the user (see 'sub' field') as below:
claims : {"nickname"=>"usernickname", "name"=>"My Name", "picture"=>"imagelinkofpicture", "updated_at"=>"2021-04-22T08:28:54.831Z", "email"=>"my@email.address", "email_verified"=>true, "iss"=>"issinfo", "sub"=>"oauth2|kakao|123456", "aud"=>"tokenvalue", "iat"=>1619080361, "exp"=>1619116361, "nonce"=>"noncevalue"}
It seems that the Barong only catches the 'email' and 'email_verified' fields and does not store any other information coming from auth0.
How about storing them in the database as a user meta data or loading them into the barong session for the frontend or other services to use them ?