The Stardust Grail by Yume Kitasei

Save one world. Doom her own.

Maya Hoshimoto was once the best art thief in the galaxy. For ten years, she returned stolen artifacts to alien civilizations—until a disastrous job forced her into hiding. Now she just wants to enjoy a quiet life as a graduate student of anthropology, but she’s haunted by persistent and disturbing visions of the future.

Then an old friend comes to her with a job she can’t refuse: find a powerful object that could save an alien species from extinction. Except no one has seen it in living memory, and they aren’t the only ones hunting for it.

Maya sets out on a breakneck quest through a universe teeming with strange life and ancient ruins. But the farther she goes, the more her visions cast a dark shadow over her team of friends new and old. Someone will betray her along the way. Worse yet, in choosing to save one species, she may condemn humanity and Earth itself.