At the moment, Roon’s ListenBrainz support is limited to the main instance at listenbrainz.org. However, the ListenBrainz server is open source and can be self hosted, or there are other scrobble server applications that can accept scrobbles submitted to them in the same format as ListenBrainz. Some examples of these include:
If the option to submit ListenBrainz scrobbles to a user-specified URL was added to Roon, Roon users would easily be able to send listening history to any of these applications or ones like them to track their listening history, without any extra work needed on Roon’s part since it already has the ability to submit listens in the ListenBrainz API format.