Would be great to have SignalRGB support for the K6 Keychron!
This device has QMK support, so you need to flash our firmware on it to allow control.
You can check pre-compiled firmwares and flash instructions on this documentation: Pre-compiled keyboards
If your keyboard isn’t on the pre-compiled firmware list, you can follow a complete guide on how to flash on this documentation: General flashing guide
Flash the exact firmware for your exact keyboard model, put the plugin file in Documents\WhirlwindFX\Plugins if isn’t a precompiled keyboard and restart Signal.