This is also standard feature for qmk based keyboards (ergodox, dactyl etc):
https://beta.docs.qmk.fm/using-qmk/advanced-keycodes/feature...
It doesn't require any special support and works in every OS.
Here is how it looks in ZSA visual configuratior, for example: https://configure.ergodox-ez.com/moonlander/layouts/ZrQev/Eo...