Hi Jouri,
Simply said, the keyboard layout only converts one character into another, so it doesn’t directly affect commands.
Therefore, a keyboard layout editor like Ukelele can’t achieve what you want.
Check out the first part of the PDF manual (from Ukelele Help) under the heading "What Ukelele cannot do".
What you need is a piece of software that runs in the background, watches your keystrokes and when triggered, translates them into system commands.
And yes, Karabiner Elements might do the trick:
Good luck!