“A client secret specific to that instance of the client application would be better. You could generate a secret as part of a bootstrapping process such as dynamic client registration. In this case, the public client becomes a credentialed client, a client that has a secret but who cannot be trusted based on the secret alone.”
In order to have multiple sets of credentials (client_id/client_secret) you’d need to have multiple applications created in Auth0 - Typically, a client application is keyed to a single application in the context of Auth0 and thus has 1 set of credentials.
I’m not sure if that answers your question or not, but the more context you can provide on your desired use case the better!