I make beer batter shrimp all the time.
Just flour & baking powder, a little paprika, and some other spices.
Pretty sure pancake batter is just flour and baking powder and a bunch of stuff added for flavor that are probably both bad for you and the general outcome of shrimp.
So first I'd use flour and baking powder and spice at your own pleasure, and of course beer.
If not I would try using beer for water or for half the water amount even with the pancake batter but I am not sure if the flavors would clash.