If Britain's the Bank, you build LARGE Kriegsmarine. If the Bank is someplace else, you built an Army !The simple answer is no Germany could not, they also could not invade with air power as they tried to gain air superiority and failed (and if they had succeeded there was no guarantee they could stop the royal navy with land based aircraft and a lack of surface vessels) There is a famous quote which i do not have to hand made by either Colonel General Franz Halder (CGS) or another member of the general staff describing crossing the channel as a "large river crossing", this illustrates how much experience the GS had in large amphibious landing operations.
I have to ask, following the French Fleet being sunk at Oran which French naval assets would Hitler have used??, how exactly would he have got the Italians to leave the med when they had to support the shipping for an Italian army in North Africa. And even with these three naval services combined how would they have hidden the preparations, could the Italians have left the med unmolested. Could Germany solve its troop transport problem and would they land a large enough force, in the face of the royal navy which had carrier born aircraft, an asset Germany lacked although Italy had a limited carrier force.
So crazy Adolf built himself an Army.
Wanna bet, that, ifEngland were to be connected to Europe by a sliver of land, Hitler still gonna go...East !?