Honestly, it's not for aid as it was your question that started my thinking about the options. I was thinking more about kids in particular. I know there is plenty of ball sets out there from Disney and others, but if you could put on a little something of anything a kid wants that would be cool. Nothing extremely complex, just general line art.
Laser etching is too expensive.
Varnish... maybe.
Acid stain... maybe.
If the ball is phenolic, it seems like there could be ways chemically, but I don't know. It could always be lightly etched in and stained too, but that is an art on its own.
We’ll call it the skid-ball.