Listrr creates lists for shows and movies based on your filters. The created lists get updated every 24 hours based on your filters, so Listrr will add all new items that match your filters, and will also remove all items that do not match your filter configuration anymore.
You can create lists with listrr and add them to your Radarr instance. Radarr automatically adds the items from the list.
You can create lists with listrr and add them to your Sonarr instance. Sonarr automatically adds the items from the list.
You can create lists with listrr and add them to your traktarr configuration. Traktarr automatically adds the items to your *arr instances.
You can create libraries from your the trakt lists you created with Listrr. As your lists get updated every 24 hours, so does your libraries.