With the controller, the Triangle, Circle, and the entire DPad didn’t work. Don’t know about the four L and R buttons, but I don’t think the games I tested really used them. Dug out an old PSOne controller and I was able to start playing without issue so it’s not the controller port itself, so I simply ordered a new PS2 controller.

https://www.amazon.com/Playstation-2-Console-Black-Pc/dp/B0000C7GHG