Being a lefty myself; and being my CZ-82 is one of my favorite pistols; I've had little to no use for any of the controls to be on the right side of the gun.
1. It's a double/single action gun. It either has a decocker, or a safety bar that allows you to safely lower the hammer. As such, I would NEVER use the safety. I.e. If I can be in double action; why would I want "Cocked and Locked" where I would have to turn off a safety.
2. Lefties have learned over the years how to release the magazine and release the slide, using their trigger finger. It's actually faster, and in my opinion better. For what it's worth, whether holding the gun lefty or righty (The CZ-82 has ambi mag release); I can't reach the magazine button with my thumb, without turning the gun almost perpendicular to me. E.g. pointing to the right. But simply sliding my trigger finger back, I can push the magazine release; put a new magazine in; use the same trigger finger to release the slide, and go about pulling the trigger. And I can do this much easier than in my right hand using either my thumb or my second hand. And being TRULY Ambidextrous myself, I've tried it numerous way. (I am dominant left EYE; so that is why I choose to shoot lefty. But I have practiced just as much with my right hand in case I need to.
So while you can go out and find ambidextrous controls, the traditional "Right" handed controls are actually easier for a lefty once you know how to use them. The EXCEPTION to this, is the safety. But again; unless you're carrying a 1911 45acp; most of the guns you're speaking of are double/single action. Decock it, and then you have a double action. There is no need to ever use the safety. And for what it's worth, the safety on a sig is really tough. While it's not hard to turn OFF the safety with your thumb; it's almost impossible to turn the safety ON with your shooting thumb. But again; it can go double action. There is NEVER a need for the safety. I have no idea why it's even on the gun. There isn't a safety on a double action revolver; why would you have one on a double action semi-auto. SigSauer doesn't have one either. Oh well; just an opinion.