I have an exterior floodlight that is switched from inside the house. I want to be able to switch it on at its outside location, as well. I don't want a motion detector light. I hope I can avoid additional wiring work. The floodlight is well protected from weather, mounted under an overhang on the outside of the house. Location is southwest USA.
You can get a remotely controlled wall switch. This comes in 2 parts. One is a switch that replaces your current indoor switch. The other is a remote control unit that wirelessly controls the switch. This approach does not require any additional wiring indoors or out. Just google "remote controlled wall switch" to see the various options available.