Prototype shortcut for "Open overlay"

It would be awesome to hold some keys and have directly the possibility to link it as Overlay.
The same way as it is with Swap – holding ⌥ key will make the link/noodle as Swap.
I find myself using too few times the Swap feature, while the Overlay is on a daily basis.
Maybe holding ⌘ will make the link/noodle as Open overlay.