Most of that would come from the platform monitor, depending on the platform, you would need to remove relevant .so or .dll files (and then you may as well remove the corresponding .jar files as well) from the /core/ext folder of the agent.
For Agent Stats, this is a lot of supportability data coming from different agent extensions.
There is a toggle for this for Browser Agent or BRTM (will depend on your agent release:
introscope.agent.brtm.sustainabilityMetrics.enabled=true
or
introscope.agent.browseragent.sustainabilityMetrics.enabled=true (after APM 10.2)
that would need to be set to false
I wouldn't expect a performance impact on the application or on Enterprise Manager for having reported these metrics, so what is the reason to want to disable all of them ?