I have two lamps wired to a 3-way regular switch: one in a hallway and another one on the staircase following it. I would like to change the regular switch with motion detection occupancy one, but there's a problem. One of the 3-way switches is in the hallway, but the other one is in the living room (adjacent to the staircase). Which means that if I change the switch to an occupancy one, it will trigger when people are just moving in the living room, not necessarily going to the staircase.

I can see a couple of solutions, but they are too time consuming/expensive:

 1. Move the living room staircase switch to the staircase. But I would like to avoid doing it because it's too much work.
 2. Remove the regular switches completely and buy occupancy sensors that are installed directly on the lamps. It's a better solution than (1), but such sensors could be difficult to match to the existing lamps.

I'm wondering if there's a solution that would be something like this:
- Replace the hallway switch with 3-way occupancy one
- Install another 3-way occupancy sensor on/near the staircase lamp
- Keep or remove the living room switch currently used to control the staircase lamp