Personally I'd freeze from raw on a flat sheet before bagging up. You could cook them from frozen if they aren't too big or defrost as needed. Think if you cook them first they might get a bit dry when you reheat?
I do either, depending on how much time I have, I fry them in oil then freeze and oven bake from frozen, or freeze raw and then fry from frozen. I don't have a deep fat fryer so frying in a pain in the bum! Generally try to do all the frying at the same time (do fish fingers after the nuggets)