My dd batted from both sides when she was little. When she was in machine pitch and in her first year of 10u she would hit from the right side, but when we were up a bit she would hit left. By the time she was 9 and playing her second year of 10u she was a full time left handed hitter. She will still switch over to rh at practice now and then, its sort of a way to show off, like a parlor trick or something. She can actually hit the ball pretty well from the RH side, but there is no benefit to doing it in games and it opens up her pitching arm to being hit by a pitch so its not something she does in games.