I see, you are suggesting a method to configure the shortcut within the app itself. I think I found an example of this in kompare - https://github.com/annulen/kompare/blob/master/kompare_shell.cpp#L438 - that seems to be the way to make this happen.

Instead of pre-assigning a global shortcut, this makes it just show up in the global shortcuts entry and lets the user enable and customize the key combination. I verified that enabling the shortcut works as expected.

That sounds reasonable. It should just be a matter of calling setDefaultShortcut instead, I think. Let me play around with it and update the diff.