most art of chaos hero has him carrying his sword in a way that makes it more convenient to unsheath it with his left hand.
left handedness had a stigma attached to it for samurai because it meant they could be sneaky and get around certain etiquette in place meant to instill peacefulness at certain times.
basically, samurai would rest their sword at the right side to make it harder to unsheath it which meant the other person/people wouldn't have to worry about them suddenly attacking them.
but being left handed throws that rule out the window.

but there is an exception to chaos hero's art in that regard and it's his ps1 demon form render.
which means being left handed might not have been important to his design or perhaps never even considered.
but i still find it fitting since chaos hero wanted freedom and if he was left handed it gives him another reason to want that since it goes against the norm of what was accepted.
it's such a small thing but it does make his design feel more unruly.