I don't see why not. Traditionally, bar-b-q has featured the same tough cuts of meat that lend themselves to braising. A full pork shoulder certainly contains some shank
The long, slow cooking at moderate temperatures breaks down the connective tissue in a similar way and the smoke from a wood-ember fire carmelizes the outside of the meat in pretty much the same way as searing/browning the exterior in a hot skillet.
With the price of good veal shanks and their delicate flavor, I would probably save those for osso buco. But, beef and lamb shanks should be excellent choices.
Hmmm, I might have try some lamb shanks, cooked the same way as ribs! Great idea.
I'd probably replace my standard rub with salt, pepper, garlic, and rosemary and substitute a nice home-made mint sauce for the bar-b-q sauce! I bet they would be outstanding.