A couple of weeks ago I found this
github.com/AlexmagToast/LinuxCNC_ArduinoConnector
Works great!
I used to use an USB arcade buttons setup to have more non-time-critical in and outputs, but this solution by Alexander works much better and has more features.
I changed for example the led's in the Arcade buttons for WS2812 led's, they can have any color now and they even can blink!
Switched the Arduino NANO for an ESP-32 with expansion board, very easy to use.
Alexander provided a lot of easy configurable options, works great and very fast.