If we're going by similarities, Ivalice is absolutely one of the closest FF worlds to Hydaelyn. The number of actually recycled monster models, the visual/aesthetic similarities (thanks, Akihiko Yoshida!) and spoilers regarding elements of cosmology certainly imply it heavily enough.
But we shouldn't discount connections to the world of FFV (once again, spoilers for 2.1 content). Hydaelyn has a lot of potential connections to the worlds of other games, and only time will tell if anything comes of it.
But we shouldn't discount connections to the world of FFV (once again, spoilers for 2.1 content). Hydaelyn has a lot of potential connections to the worlds of other games, and only time will tell if anything comes of it.
