Actually, I like the concept of being able to dual wield pistols. Yes, you need two hands to reload, but there's also such a thing as a holster. You could have them in a chest rig if you really didn't care about the safety of others, or just at your sides. The animation would show them aiming and firing them one at a time, since they would of course be impractical to fire at the same time. I think this would add an interesting gameplay element, since now there's a new tradeoff. Using two pistols means you get two powerful ranged attacks in quick succession, but the reload time is very long.
Firing them with one hand is perfectly doable, assuming you aren't firing ridiculous hand cannons, and combat encounters take place well within a reasonable range to be accurate while using such a method.
It's really not as impractical as it sounds. Dual wielding pistols is only impractical in modern times since we have detachable and quick changing magazines that hold 17+ self contained rounds, as opposed to a flintlock or caplock that holds 1 or 2 (sometimes more, but not by much) internally and the charge has to be manually loaded. We no longer need to make any tradeoffs to have multiple quick shots while sacrificing accuracy and recoil stability. Having those two quick shots would be great if you lived in a time where that was all the current technology allowed.