It's ever-so-slightly-possible-but-not-really-probable that Faer may have heard of Viara, or heard of some chick who drops elves off in the forest once in a while who are looking to join the Dalish. Because she does that. Because she has a huge soft spot for elves in general, and especially elves in peril and plight.
Not that she'd tell you that, or treat an elf any differently than she would a human. If they ever did meet, though, she'd probably try to make him talk. Because she likes to listen. And she doesn't care if you're an apostate or Andraste herself, really, but the shapeshifting thing would definitely "come in handy"