Set-pieces have been subjected to a drastic change in FIFA 17 and penalties have seen the biggest alteration. They can be difficult to grasp but the change allows for more variety in choices of penalty kicks.
To take penalty kicks, you now have to choose direction and power, with how long you press shoot having a precise impact on where the kick is placed. You can now also use the left stick to move your starting position which will alter the angle at which the ball goes into the net.
To begin your run up, move the right stick in the direction you want your shot to go. Then, as your chosen player begins his run up, hold the shoot button (circle/B) for your chosen amount of time, depending on how high you want the kick to be. Penalties will sometimes show an arrow that will change color as you run up and hold shoot. The nearer the arrow goes towards red, the harder and higher the shot will be. Having the ability to choose exactly how hard you hit the ball, and where you want to place the shot, allows you to be unpredictable with your shot. You no longer have to take the perfect penalty to beat the goalkeeper. It may take you a while to get used to penalties in FIFA 17 but they will certainly benefit you in the long run.