User blog comment:Mr. Nightingale/Is there hope in Once Upon A Time for HTTYD?/@comment-24667521-20141027030808

If you mean a canon appearance of the HTTYD characters in OUAT, then the answer is no, because OUAT is Disney property.

But if you're just talking about a fanfic AU thing, then of course. XD We've got the Storybrooke AU for that already. XD