Photo credit: Lets Go Digital
Sony filed a patent on June 20, 2019 for an ‘input device’ and it was just published on December 26, 2019 in the WIPO (World Intellectual Property Organization) database. The patent sketches reveal a missing PlayStation button, along with two buttons on the left and two on the right rear. Both sides have a large movable button that you can be slid up and down, along with a smaller button that can be pressed. Read more for the patent sketches and additional information.
The large movable button can be used to extend the handle at the bottom, enabling you to quickly adjust the game controller to the size of your hands. A pressure sensor can be found on the small button so it can accurately detect whether the button partially or fully pressed, allowing the game to automatically adjust to this. All four controls can easily be accessed with your middle finger.