I’m lefthanded but since I got my first PC I was using mouse in my right hand and got used to it. If I were you probably I’d invert it. Move on some extreme right letters to have more buttons to press but then you might lose some modifiers like alt, shift and control. I know that one of my friends was playing on numpad but it’s not enough buttons there. Definetely using WSAD might be hard. Other option is any keypad. Maybe Razer can create Orbweaver for lefties.
I’m leftie, but i write with my right hand because i got physically forced to learn that by my parents. Same with pc’s, when they first came out there really wasn’t an option. There was one mouse and one keyboard, use it or beat it.