Super Xevious and Xevious doesn't use a 4 way stick. Uses a 8 way stick. You can convert it into a 8 way on the Partycade. I done it before. Parts on Amazon. I don't know they corrected this later for the newer models or not.
Sinstar doesn't use a 8 way stick. Uses a 49 way stick. But on the Partycade there is a USB port for a controller. Newer models only.
There are some other fuck ups that they done.
You can replace the sticks and whatever. The hardware doesn't have any issue on the replacements. For example 49 way stick should work. Might have to mod the wires on the stick though.
What I heard. You can swap games board. For example Frogger board from a CounterCade can be use on a Partycade. As long the buttons are there. Time Pilot 84 uses two buttons.