Hi everybody,
At WHO we have been working on an application to synchronize metadata (and data) from one to one or multiple other DHIS2 instances containing similar or different metadata.
You can schedule the synchronization to occur automatically at regular time intervals. You can select subsets of data elements (or any other type of metadata) to be sent very easily!
We have just release the latest version, sharing the link to the release in case it helps: MetaData Sync app 2.2.0 now available
It does a bunch of other things like sending data from one DHIS2 instance to another one with different metadata (making all necessary transformations on the fly) or scheduling data synchronizations as well.
Hope it helps!