“And so we met, my spirit guide to this new and awful Eden, and Miss Jamie Oldcourse became the first of my Helpers. For in this new world, one cannot navigate without them; the rules are particular, so peculiar and so dissimilar to the fey’s.”
It’s not a precise example, but I just finished Except the Queen by Midori Snyder and Jane Yolen, and it was interesting enough that I decided it at least deserved a mention here.
Serana and Meteora are fey sisters, banished by the Queen from their home in the Greenwood to separate cities in the mortal world, and immediately thrust into a dangerous situation (unbeknownst to them, initially) – on top of the confusion and danger of trying to adjust to human life. This is both an example of the “reverse Girls Underground” story (where the protagonist starts in what we’d consider the “otherworld” and comes to the mundane, human world), and the rare double-protagonist.
The sisters have companions, including animal ones, and what seems to be an Adversary (though there may be a more threatening one). They have a goal – each to save a wayward young person who ends up in their care. While they have not forgotten themselves, they have lost their former selves in new, very changed bodies. They must expose the truth of the situation and fight the forces that wish to take even more from them.
Even so, it does not quite hit enough points to make it a solid GU example. Nonetheless, it is a great read, an interesting format (with point of view shifting between the sisters, with occasional glimpses into the lives of the other players), and delightful in the details of fey creatures adapting to our world.