This isn't a mod integration but there's already a vanilla extension, namely sending waypoints over chat. It would be nice to have a feature to see loaded chunks on the world map (ideally, different colors for entity-processing, lazy, and border chunks). This feature would be particularly useful for technical players who build chunk loaders but it could potentially be useful to server admins as well.

This is available in journeymap 6.0.0 beta natively for server admins if journeymap is also on the server.