Only capture emails that are cc'd into a group mailbox

We’re testing the emails and activity functionality but don’t want the system capturing every email - as some are confidential. We have a group mailbox and tend to copy that in when it’s ok for everyone to read the email.
Is there a way of setting up a rule that effectively says to only capture email if xxx is cc’d? Or make an email private (to user who sent it) unless if xxx is cc’d?
Thanks

I would think you’d want to look into making E&A tied to the group mailbox itself?

Thanks. I did try that but it isn’t capturing any outbound emails from individual users.

AH because you’re not doing send-as/on-behalf of the group email for outbound. Curious if you tried that?

Basically then emails would always come from the group email but say “so and so on behalf of group” But not sure that is something you’d want - all correspondence would then be in the shared mailbox.

Yeah, I did think of that but it’s a big change to how we communicate with clients. I guess it’s just going to come down to a question of what the easier compromise is going to be. thank you