Help with Shelly wiring into UK Switch

I was wondering if someone could help me with installing a Shelly device behind my uk light switch please?
I was going to install in the ceiling rose as I assumed I had no neutral but to my surprise, the wall switches do have neutrals. I’m pretty confident with L, N, I connections. I am however unsure of what to do with the SW and O connections.
Attached is one of my light switches. It is a 2 way switch - there is another one at the bottom of the staircase.

If it’s the Shelly 1, it looks like 0 & 1 are your switched contacts. This has some explanation although YMMV when playing with mains!

The bad news is, if that’s correct, I can’t see how you would make a typical UK 2-switch hallway type arrangement work. You would need a double poll switch for that and the Shelly 1 is not one of those!

I can send you a wiring diagram (when I draw it out) but do you think the shelly device will fit into your backbox?

Edit: just noticed this thread is 1 year old! Did you get this sorted out?