On most of my vehicles the drain plug sits reasonably low and I wouldn't trust a JB-welded socket to adhere to it long term especially exposed to debris, flying objects, water, salt, etc... Personally, I'd just go with a new drain bolt of the appropriate thread size/pitch with whatever head size or square drive I desired. My fear would be that the socket will be long gone in a few months (due to applying to two shiny surfaces) leaving a messy hex head with JB weld slathered all over it that a socket won't attach to.
Keep us updated if it works though!