I actually think it's becoming seemingly likely that Dark Link will be in this game, props to you for predicting this a while back. However, nothing seems to suggest that Dark Link is actually evil, we now have learned that Hilda isn't in fact evil, such is what I originally thought. Due to the way she referred to "Your Link" I think that this Link may not be evil. Let's remember that Dark Link in Zelda II wasn't necessarily an evil being but a test of sorts.
It could be possible that Dark Link, or a possible Lorule counterpart to Link, is an evil figure but I wouldn't count on it just yet.