We don't have any documentation on moving to Auth0. Here's info on import users to Auth0: https://auth0.com/docs/users/import-and-export-users but I haven't tested that. Looks like you need to build a JSON file to import users: https://auth0.com/docs/users/import-and-export-users/bulk-user-import-database-schema-and-examples
You'll probably want to read directly from the FusionAuth database.
Not sure about the other configuration.
Sorry to hear FusionAuth didn't meet your needs, but I hope your app is a wild success!