I didn't know where to post this, I figured dragonborn was most relevant. So I accepted the quest to find the enchanted bow schematics from dawnguard, and the quest log says its in hrodulf's house. After doing some research online (because i had no quest marker)I found that hrodulf's house was in the dragonborn island. The quest seems to put these schematics in random places, but into a different dlc? Had anyone else found dawnguard crossbow schematics in dragonborn turf? Or can anyone confirm this isn't a bug? I'd rather start a new game than spend hours finding that this was a bug.
I got the quest to go to Hrodulf's house for the schematics too. I got it before i even started Dragonborn, and I didn't even see an arrow sending me anywhere, so I thought it glitched. But I got on the boat, went to Solstheim, made it my active quest, and it sent me straight there.