Hello,
The Vulnerability scan depends on syscollector to find the list of packages installed on the system, for this reason, it needs an agent installed on the system.
At the moment agentless monitoring can perform integrity checks and you can also collect logs via rsyslog. Check this documentation for more information:
https://documentation.wazuh.com/current/user-manual/capabilities/agentless-monitoring/index.html
https://documentation.wazuh.com/current/user-manual/capabilities/log-data-collection/how-it-works.html#remote-syslog
Regards,
Daniel Folch