I have always used my mouse on the left side of the keyboard despite being right handed. I think it comes down to being a child learning to play PC games and no

I have always used my mouse on the left side of the keyboard despite being right handed. I think it comes down to being a child learning to play PC games and not really having the dexterity in my left hand to control WASD and the various keybinds properly with my left hand. So I adjusted to mouse on the left and right hand on the keyboard. It does make it annoying to type and play games at the same time though since I usually have to move the keyboard pretty far off center to get comfortable and if I want to type I have to move it back to center first.