How to add shortcut for enter key in Ubuntu?
You could use xdotool to hack simulating the enter key as follows:
xdotool keyup control+e key return
The keyup statement releases your shortcut key before sending a return to avoid interference from holding Ctrl.
Bind that command to Ctrl+e using "Settings" - "Keyboard" so it gets executed when you press that key combination.
Note this works on Xorg only, not on wayland (default in later Ubuntu versions).