I'm a lefty as well. I use my right foot for the sewing pedal, but I do use my mouse with my left hand. I didn't switch the buttons, I use the middle finger of my left hand to click it. I use scissors left handed, but when I'm eating, I cut with my right hand. I don't go through the silly changing fork hands like most Americans, I eat with my left hand.
And don't get me started on scissors! Ours are more rare, and they usually cost more!!