As you’re probably aware with your existing products, there’s a slight sound delay if you group speakers and share a tv signal. So, whilst the two soundbars can be set as Room1 and Room2, and each can play the sound from their tv, as soon as you group them they’ll go out of sync. 
Q1:physically, yes but as Room1 and Room2. 
Q2: yes.

Q3: not with both speakers playing in sync.

Q4: yes, playing in sync. 

 

I have a friend who has this setup. With two PLAYBARS. His Arc is on the ‘movie’ TV in his living room, but I’ve watched a lot of TV and gameplay on these TVs, using the soundbars. Usually one is muted, just because being next to each other, there isn’t much call for both a game and a TV show audio the same time. But while each one is it’s own stereo setup, he’s grouped them when playing music, they sound good, although the stereo separation is a bit muddied.

@nik9669a & @airgetlam

Thanks for your replies.

Is it possible to have a single Arc connected to (2) televisions via HDMI eArc and optical?

If so - how would you “switch” inputs on the Arc?

Arc has not an optical input. In order to connect an optical cable, you need the optical-HDMI adapter. So the simple answer is NO, as you don't switch inputs, you just use the adapter (for optical) or not (for HDMI).

And if you were to try, I’d connect the TVs to some sort of switch, and the switch to the Sonos Arc. 

OTOH, I wouldn’t want to try this, it is fraught with potential failure. Too many pieces. And, I suspect it would be difficult to find an ARC passing switch that also had an optical input. But I’ve never looked. 

I believe you don't necessarily need optical, as both TVs should have HDMI-eARC/ARC. Then, you should look for something like this:

https://feintech.eu/en/collections/hdmi-switch/products/ax420-hdmi-earc-switch-2x-tv-1x-soundbar