The soundtrack for Shadowbringers patches 5.1 – 5.5. is called Death unto Dawn and will be released at September 15. The new album has 84 tracks and will cost 39,99 euro. You find this new and all the olders albums with soundtracks of Final Fantasy 14 on the Square Enix Music portal.
The soundtracks of A Realm Reborn, Heavensward, Stormblood and many more can be found on Spotify as well. You also can follow Masayoshi Soken, the beloved lead composer and sound director for Final Fantasy 14 to find all available releases.