Mechanical Keyboards

Touch typing requires the use of both hands, and as qwerty was design to try and spread the use of each side of the keyboard (stop typewriter arm jamming) you should be able to use qwerty whether you’re left handed or not.

I’m left handed, but right hand trained. So I write with my right, mouse with my right, but throw with left, knife and shooting hand is left.

Having worked as a banking clerk at one point, I’ve learnt to data entry numbers with my right hand, but maybe I’ll be hugely efficient if I can type numbers with my left and keep my right hand on the mouse.

To add to the above, left-handed people also don't write from right to left, unless they write Hebrew, Yiddish, Arabic or some other right-to-left script, and they don't see the world in a mirror image, hence no need to actually mirror the key distribution. What does matter to them in terms of keyboard organisation is that something like the arrow keys or number block are near their dominant hand.