Instead of making it an additional Ctrl key, you can also make it a new separate modifier key with XKB[1]. I've found this very useful over the years for WM-related key bindings, leaving the other modifiers for applications.

Tangentially, I really loathe how Wayland has no alternative to this. I'm expected to configure keyboard layouts in every DE or WM I use, which is a much worse UX.

[1]: https://vincent.bernat.ch/en/extending-xkb#attaching-symbols...