if Hitler had tried sea lion seriously the war would have been over sooner as it would have been an Epic Epic kerb stomp
The German invasion plan relied on barges and capturing a working port even the iraqi's managed to put um qusar out of action.
without a port getting any decent amount of stores ashore is impossible let alone tanks or artillery. without specialist kit landing craft tank landing craft a floating harbour pulto the cross channel fuel pipeline etc etc.
you've effectivly got two or three divsions of light troops with what they jumped climbed out of gliders or climbed out of barges with. plus what they can capture not much.
Against truly impressive fixed defence lines with plenty of artillery and tanks ok not very good tanks but as you have no tanks your screwed.
The Royal navy is going to be making mincemeat of the invasion fleet its simply numbers.
The german plan was to mine the channel to keep the home fleet out slightly impractical.
germany loses all it's forces committed to the invasion.
English channel Choked with german dead.
One warship gets in amongst slow moving barges full of flammable stores game over