You can disconnect red wires using the circuit wire connector tool in reverse mode (right click drag), and green wires with the circuit wire connector tool in alt-reverse mode (hold shift and right click drag). Although this only removes red/green wires where there are also copper (power) wires. Does that do what you want?
It doesn't work, the shortcut is already used in-game to copy settings between buildings. Even if you change the shortcuts, you can select the buildings, no disconnection occurs.
