I didn't have dysgraphia as a kid. In fact I was ambidextrous and wrote quite well with both hands. I also wrote stories, and would spend hours writing them down by hand.
But when I was 23, I had a massive mental breakdown/autistic withdrawal, which affected many skills I had by that time--computing, some math skills, playing musical instruments, drawing and handwriting. Since then, I don't write with my left hand, except on rare occasions when that ability seems to awaken in my brain for short spells. And now I have standard motor dysgraphia. if I take my time, I write OK, but my hand gets tired easily and my concentration fades, and it just devolves into back-ward slanting scratches.
When I was dx'd with AS well after my breakdown, my dysgraphia was not considered part of my AS, as I didn't have it until after age 23.