You can configure auditing options (global, database-wide, and per-login) for each companion server on a per-node basis. That is, each companion has its own auditing setting. Global options are not synchronized between the companions.
During failover, database-wide options are audited as they are currently configured.
After failover:
Auditing continues to enforce the global options, and database-wide options run the same as before.
Users are still allowed to set their database-wide options.
The audit options of the local domain are used for both local and remote logins (that is, either the failed over primary companion or local secondary companion logins)