I am working on a project where we will develop a Rest api for a mobile app that uses Auth0 for registration and authentication of users. The client that we develop the api for wants to provide custom ui strings for the different languages the app will support (for the moment English, French, Spanish and Vietnamese). They claim there are api calls where you can add these custom strings for the login page and the verification email. I have looked though the Auth0 apis and documentation but have only found info about this if you use MFA. If you want to use Universal Login without MFA is this possible?