Unfortunately, we haven't tried Metronic Vue with Auth0 Service, we will try it and consider an opportunity to implement it in Metornic.
As far as I understood Auth0 provides an authentication API so to implement it you can try to update our auth module's actions with your auth0 service requests. Please check auth0 official doc for more info about implementation.
Regards, Lauris Stepanovs, Keenthemes Support Team