I know of one local duck hunting legend in my area who regularly shoots from both sides with his O/U. He practices on the skeet range by shooting the birds from the high house from his right side and the birds from the low house from his left shoulder.
He actually switches sides shooting doubles!
The guy is quite substantial
And his hunting buddy told me that he cannot move easily from side to side in the duckboat so had to develop his ambidexterous shooting style to shoot at the ducks!
And he is very good on the skeet range. I am told he is deadly on the quackers too.