I am looking for a smart switch with quite a lot of requirements which I’m finding tricky to shop for and I’m wondering if anyone has suggestions of products or alternative solutions to what I’m trying to do.

Downstairs I have a ‘dumb’ triple light switch (like this) which controls the outdoor porch light, the downstairs hallway light, and the upstairs hallway light. The upstairs hallway light is in a 2 way configuration, with the second switch being a single gang switch upstairs.

I would like a way to control all three lights from home assistant (using zigbee2mqtt), while retaining the ability to control all lights from the switches even when home assistant / zigbee network goes down (which removes the option of replacing the upstairs switch with a smart switch that can control the main switch via automations). A bonus would be to be able to dim the hallway lights, or at least the upstairs lights. My current ideas are:

Solution 1: find a 3 gang, 2 way zigbee switch to install in place of the current switch

Solution 2: use a 3 gang ‘dumb’ switch in combination with zigbee light relays - could use a 2 gang one in the downstairs switch and a 1 gang 2 way one in the upstairs switch

Solution 3: get an electrician in to separate the porch light and move it closer to the front door on a single switch, then I would need to find a 1 gang switch for that, and a 2 gang 2 way switch for the upstairs/downstairs hallway lights.

To add to the challenge, it is an old house with 25mm deep back boxes, so smaller depth smart switches are preferable - but I have accepted that I will probably need to get an electrician in to make the back boxes deeper.