The Metadata module adds a fully customizable metadata tab to the layer configuration, allowing the user to have the layer configuration and layer metadata in one central place.

Bulk Operations can be done via the Metadata Rest Service.

The layer metadata can be exposed by the Catalog Services for the Web (CSW) service, from there periodically harvested by GeoNetwork . Have a look at the INSPIRE metadata configuration using metadata and CSW tutorial for an example of matching metadata and CSW configurations that can be harvested by GeoNetwork.