If you don't already have this problem it's not really relevant.
- Uniformly describes different key codes across different terminal emulators and platforms;
- Sends the codes which native platforms support, but the terminal protocol does not, via a custom prefix. It gets decoded on the Emacs side, and mapped back to a native-matching key code. You can press fancy keys and have a uniform reaction in Emacs, no matter if you're using a local graphical Emacs, or remote Emacs in a terminal.
I confirm, this is a great approach; I used a much simplified version of it with WezTerm and remote Emacs.
I switched to Colemak about 15 years ago and thought it would be a good idea to rethink all my Emacs keybindings, since my muscle memory was shot in that transition. (I don’t recommend this in hindsight.)
I have yet to get a terminal working fully like the GUI. Partly because I refuse to install a third-party key mapper.
Anyway, just tried this and Alacritty. It’s the closest I’ve got to fully working. My guess is another hour of tweaking and I could maybe get all the way there.