Yes, directly connected and the snap shot would get building terrain. Bit like a snapshot on a building hexside. Can you EVER see the whole of tgat hexdide though?
BFP have produced a few such hexsides on their maps. The whole idea was to block LOS through that hexside without making the two hexes part of the same building, with the implication of being a single 2 hex 1.5 level building as opposed to being 2 single 1 hex level 1 buildings. As no LOS then no Snap Shot (and I think no bypass along that hexside).