In general, it’s easier with a receiver with a tape loop. Note that CONNECT and it’s current version, the Port, are stereo devices, and will not handle anything beyond stereo. 

Has any AV receiver had a tape loop in the last 10/15/20 years? These days you can often accomplish the same thing if the AVR has analog Zone2 pre-outs that can be configured to play a source other than Zone1 at a fixed level, but yeah, not quite as easy.

OP, what exactly are you looking to achieve? It’ll be easier to make recommendations if we know what you want your system to be able to do.

In many cases, zone 2 pre-outs are disabled to play digital inputs of either HDMI or optical types. Depends on the AV receiver of course, but might be an issue, depending on what the OP wants. 

Exactly; and most requests are in different order, from people having an AVR wanting to integrate it into Sonos, via Connect. An AVR may turn out to not even be necessary in this case.