While I’m certainly happy a standard set of keybinds exists for things like copy and paste, some people prefer to use other keybinds out of preference or for accessibility reasons.
Personally, I like using emacs-styled keybinds but since the key theme mechanism was removed in GTK4 there is no longer a way to do this (at least, that I know of)
When I create a custom shortcut under mouse and keyboard, if my chosen keystrokes overlap something already there, I get an option to override. This is an easy way to start an application or execute a command.
From your question it seems you need a navigation function… as in a certain text editor. There must be a way to insert those moves into the command box. I have reached the limit of my knowledge.