When using multiple authenticators with OR-logic, first try the authenticator client requests in the handhake response

https://mariadb.com/docs/server/reference/sql-statements/account-management-sql-statements/create-user#authentication-options says:

If more than one authentication mechanism is declared using the OR keyword, the mechanisms are attempted in the order they are declared in the CREATE USER statement. As soon as one of the authentication mechanisms is successful, authentication is complete.

This leads to an unoptimal situation (assuming user account uses authenticators A and B in that order): Client gives password for authenticator B and asks for B in handshake response, yet server tries authenticator A first. Only once it fails, does the server switch to B.

Server could try B first, assuming plugin B is loaded and the user account uses it.