I've only used it for testing/debugging so I didn't need any of that capability. I'm not sure why they recommend avoiding exec in the config. Since it would still be under the same user session, dbus things could get wonky. Nested hyprland will automatically create/use ~/.config/hypr/hyprlandd.conf and you'll def want to have unique keybinds. If you haven't gone too crazy with keybinds, just changing the main mod key (I used capslock) in the nested config should take care of most things.