Yup. I was thinking about this a few days ago. There is a small trickery with how the engine manages weapons and shields. Basically, there's a bone called Shield, which carries the function to tell the engine where shields and left handed weapons (in dual wielding) should appear during the animations, both sheathed and unsheathed. It's very easy to change this bone position to the back of the player, but then it will always stay in that position. The solution for this is unclear for me. We'd have to create a new bone in the back or use one of the existing ones (quiver, bow, weaponback -2H-) and somehow tell the engine to move the shield mesh from that bone to the left hand one. I don't know how to do that and I think those kind of skeleton interactions are hardcoded into the engine. *edit* Looking the OB mod.