Z-wave/zigbee 3-way switches. Use a controller of your choice.
Home Automation
Home automation is the residential extension of building automation.
It is automation of the home, housework or household activity.
Home automation may include centralized control of lighting, HVAC (heating, ventilation and air conditioning), appliances, security locks of gates and doors and other systems, to provide improved convenience, comfort, energy efficiency and security.
Warning: Working with electricity can result in injury, property damage, or even death if it is not done properly. Please keep this in mind while assisting others. If you are not sure about what you are doing, hire a licensed professional.
Rules
- No abusive behaviour. This is a forum for friendly discussion; personal attacks will not be tolerated and you will be banned without warning.
- Referral/affiliate links are NOT ALLOWED!
- NO POLITICS! There are plenty of other communities to discuss them; this is not one.
- When posting project details must be included. Posting a video or image without detail will result in a removed post and may result in a ban.
- Crowdfunding links are not allowed.
- Reposts, low-effort content and karma farming may be removed at the discretion of the mods. Posters may be banned without warning.
A couple options:
Install smart 3-way switches (or dimmers) using ZigBee, Z-Wave or Matter protocols instead of the dumb "analog" switches. You'll need a smart hub that acts as the centralized controller. The switches still handle on/off at the wall (or dimming if you want that as well), but you can use voice control or routines to adjust them.
Add smart relays behind the switches. I believe Zooz has some smart relays that use Z-Wave. Again you'd want a hub that can talk Z-Wave. There are Wi-Fi versions like Sonoff or Shelley, but you said you want to avoid that.
I’d recommend Sonoff zbmini L2