You'd have to ask SwinginSoriano about that, especially for Major Leaguers. In the next update, I should have all MLB players updated hot/cold zones finally done.
For minor leaguers, I just stereotype and give lefties hot zones down and in, and righties middle in hot zones. I've never found that batting a ball in the hot or cold zones makes much of a difference, so I don't put too much stock into whether players have truly accurate zones.