That may work fine with Percussion guns, but its nice to have a stock and lock between your eyes and that flintlock when it goes off. I recommend that LH shooters find a LH flintlock if they are going to shoot flint. After they get used to the KlatchBoom of the action, they can shoot either right or left hand flints without much difference. But its pretty hard on the learning curve to have that distraction so close to your face. For most percussion shooters, making the transistion to Flint is hard and long enough to do, without the added complication of shooting a gun with the action on the wrong side. Hand a LH flintlock to a RH shooter and get their impressions when they have shot it a few times, if you don't want to believe me. All those RH folk who tell us LH people " Just to use a RH action " sing a different tune when they have tried out their own music.
For what its worth, I am a lifetime LH shooters, but have had to shoot RH guns most of my life because they either didn't make them in LH, or I could not afford a LH gun. I was trained on the piano for years, so I have quite a lot of dexterity with both hands. Its no that I can't shoot a right handed gun; I just am more comfortable shooting a LH gun.