Hi Franco,
Maybe if I draw what I am asking it might be easier. Its a two part question so lets start with part 1:

I have a monitored hosts with applications and services running that include things like:
- IIS
- MSSQL
- Oracle DBMS
- Custom Applications
I would like to know if the Agent can monitor a custom log file (a), process it via the Logcollector (b) and forward those logs to Wazuh. I assume that the agent itself will want to do some pre-decoding of the log files before it is sent on to the server?
I draw this conclusion based of the the agent config, where you have to specify the format of the file you want to monitor, for example:
<localfile>
<log_format>iis</log_format>
<location>C:\inetpub\logs\LogFiles\W3SVC1\*.log</location>
<location>C:\inetpub\logs\LogFiles\W3SVC2\*.log</location>
</localfile>
If I can get that part sorted, then I can create custom dashboards for my services and application to monitor them and also alarm me when there are problems on the system. Which would be absolutely terrific.
The second question is that File Beat has default dashboards that you can import into Kibana, such as:
I know management will look at this and say "Why can't we use some of these dashboards? Look, IIS is already there, just turn it on."
I have tested this by setting up both the Agent and File Beat on a host:
I don't think anybody would easily accept the idea of setting up 2 different monitoring applications on each of our hosts, File Beat and Wazuh Agent.
Is there a way to simplify the the setup so that the Agent alone will collect all of the logs required to drive the Dashboards, such as the [Filebeat IIS] Access and error logs ECS?
When I look at this layout in the documentation, it would seem so:
I would assume that if I can collect the required logs, I can get those logs to Wazuh via the agent, then output the logs to the raw data log. From there Filebeat can pick through the logs and populate the data required for the default dashboards.
I hope this makes a bit more sense?
Kind Regards