The ball placement in your setup position varies with the club you select. From a flat lie: Play your short irons (wedges, 9-iron, and 8-iron) in the center portion of your stance. These clubs have the most upright lie angles. They must be swung at the steepest angle, and you should take a divot in front of the ball.
https://www.tripsavvy.com/golf-setup-position-1564424