As for attacking France, I only attack Paris.
As for SZ 93, I only need 2 air units (1 Fighter, 1 Tactical Bomber) and with that, I outgun the French Navy. (Though, I do send 2 fighters and 1 tactical, for better odds, I just dont have too.) 2 Fighters, Tactical from W. Germany.
W. Germany to France
France to S. France
S. France to SZ 93
SZ 93 to SZ 95
SZ 95 to either S. Italy or N. Italy