The GP2040-CE (Community Edition) is a controller input firmware for the Raspberry Pi Pico and other boards that derive from RP2040 microcontrollers. Among a robust list of features, the GP2040-CE also has its own per-button LED support. You can view pre-set static button colors, pre-programmed animations, and console specific button colors!
Learn more about GP2040-CE's LED capabilities here:
https://gp2040-ce.info/rgb-leds/ 
2 Inch (50.8mm) Harness
This 2 inch (50.8mm) harness has two 3 pin JST connectors. This length typically represents an addressable LED daisy chain.