A left handed NES controller is a modified controller that's basically rewired to work upside down with the D-pad in your right hand and action buttons in your left. This mod helps left handed people better enjoy their favorite NES games!
The idea isn't mine but I was asked to make an alternative to the ones available. My take on this focuses on using a small custom PCB that rewires all the controls and all you have to do is desolder the chip from the NES board, solder it into the mod board then solder that board onto the NES controller board using either scrap leads or 30 gauge wire and in no time you're gaming lefty!
I designed two mod PCBs, one solely accomplishes turning a controller into a left handed one and the other uses 4 dual SPDT switches to give the user the option to switch back and forth between a normal layout or a lefty layout.