Anytime you group a speaker to a Sonos home theater setup while playing TV audio, you will experience a minimum 75ms delay from the grouped speaker. How noticeable this delay will be is largely dependent upon where the grouped speaker is located in relation to the home theater setup and how sensitive your ears are to the delay.

Test it out for yourself and see how it sounds.

​@Satchdds 

The delay ​@GuitarSuperstar mentioned can be eliminated by using the „tv dialogue synchronization“ option. Setting it to level 2 or 3 for me works fine. TV sound plays in sync on grouped rooms and there’s no remarkable delay on the video. 

Remember some people are more susceptible to noticing lip sync troubles than others. This could work for you, but I’d not say you can “eliminate” this delay.

Ok, you’re right… seen from the technical side of course it’s not just eliminated without causing a delay at another point, the video. 
But indeed on many systems I never got a remarkable lip sync issue and many users also gave that as feedback. So in the end I‘m really ok with giving that as an advice. 
But of course it’s a good hint to mention that there will be a lip sync delay any user has to check himself if it’s ok.