Ashes and Blood by Katie Zaber

A mystical tree captures the attention of Megan & her friends, morphing the environment & transferring them to an exotic planet. Saved from deadly beasts by hunters, Megan finds herself stuck in a rural town still maimed by the plague. A chance encounter with a familiar face gives Megan & her friends some security during their adjustment to this new world. While settling into promising lives, they are attacked & stalked by planet Dalya’s humanoid inhabitants, who focus solely on Megan.
One dark night, after a magical attack, the Fae King’s knight is sent to fetch Megan for a reason she can’t possibly guess. When she wakes up a prisoner, she learns that there is much more to this strange place, & it is oddly more like home than she ever would have expected.
The more Megan learns, the more she realizes that finding a way home is insignificant compared to everything at stake.