It's tough to tell until a kid grows. A friend growing up was an awkward lefty who was terrible at best. But he loved the game and kept grinding. I used to catch him in the pen in his yard in exchange for riding his half pipe ramp. Kid didn't make the HS team the first few years. Then he grew to 6'4" and looked like a man. He made it to the majors before an injury cut his career short.
I'd look at his bat speed before anything right now. Someone posted a video here a few weeks back and the first thing I thought was the kid needed a lighter bat. Bat speed will improve control and ability to hit balls on time.