I'm left handed and right eyed (don't see out my left eye!), which makes aiming at anything fucking ridiculous...
In school i was called cack handed as i couldn't hit balls with bats or catch balls very well. Close up distance calculations are much slower for me as my brain has to take forget about my left eye info and re calculate what it thinks my left eye should see and relay that info to my hands and right eye! IT's not the hand that's cacky, it's the eye
I've been a calligraphy artist for years and managed to never smudge writing with my left, i don't curl round, i position my wrist underneath the line of writing. I can right easily right to left in mirror writing and have no problem writing upside down too.
I use a mouse in my left hand, but still choose to use the left and right buttons as designed rather than swappign them
Left handed scissors are anoying for me as i need to see the cut with my right eye not my left. So i tend to use right handed scissors in my left hand.