Obviously you would sink atleast one of the battleships, maybe even two. My point is if UK buys inf heavy you would avoid sea lion, if they build boats and/or big time in africa, send in the sea lion.
I mean really, if UK buys 9 men on turn 1, why even bother facing them as there no threat, its time to eat some russia!
I think I personally will purchase 1 trans, 1 DD, or two trans and 5 inf on turn 1, hiding atleast the trans in the baltic maybe even the rest of the boats while sinking all the UK boats I can without huge risk, probably leaving 1 BB, 1 Cru in the atlantic. Then on turn 2 if the UK builds say, a minor IC, or 3 tanks out of south africa, move up the fleet drop more boats and dance in London on turn 3. Keep in mind too, you don’t need all transports as your airforce is larger than the UKs, not only that but 13 IPCs gets you two inf and a trannie, 10 gets you a fighter. Yes the inf are better but the fighter is more versatile after you take London.
What I’m saying is, going hardcore sea lion isnt that great of an idea, but the threat of it forces the UK to react and gives you an advantage.