That’s a nice idea. A possible, caveman style starting point:
grep -Po '^\s*bindm?=\K.*' ~/.config/hypr/hyprland.conf | column -tl4 -s, | fzf
and the Sway equivalent while at it:
grep -Po '^\s*bindsym (--\S+\s+)*\K.*' ~/.config/sway/config.d/default | column -tl2 | fzf`
not really that nice to look at, but it serves the purpose when I forget my key binds.
It should be easy to also extract descriptions from a nearby comment and replace key names with their symbol, but I never bothered.