The lyrics are all in Japanese, so English speakers may have trouble making them out.
Lyrics are from Michael Christopher 'Koji' Fox and Natsuko Ishikawa. He's also known for his background music for games like Drakengard 2, Mario Hoops 3-on-3, and Mario Sports Mix. The music for the song comes from long-time composer Masayoshi Soken, who has worked as composer on Final Fantasy 14 since the MMORPG's inception. That's not informative at all! However, we do have information about the talent behind the song, as revealed during the Final Fantasy 14 Digital Fan Festival. There's no official title for the song in the Endwalker trailer. What was that song? What song is playing in the Final Fantasy 14: Endwalker trailer? This trailer contained a number of new story reveals, the return of some fan-favorite characters, and some exciting new features.
One of the most exciting reveals from Friday's Final Fantasy 14 Digital Fan Festival keynote was the full version of the Endwalker expansion trailer.