Not in 1940. At that time the Luftwaffe had very poor anti-ship training - as the lack of success at Dunkirk demonstrated. (Later, of course, the Germans performed well with the VIII Fliegerkorps being especially successful around Crete.) Additionally, given the confined waters of the Channel, the ludicrous plans that the Germans had for the landings - they were to tow Rhine barges across which had such a low free board that a destroyer would have been able to sink the thing with its wash without firing a shot, together with the fact that at night the RN would have been able to operate at leisure - the KM at that point due to the losses in Norway had damn all surface ships with which to interdict the RN.
Anyway it's all academic. The RN would have defeated Sea Lion; the RAF stopped from from even trying.