Need it too!

Yes, please incoming and outgoing mails bcc for journaling functionality.

I need this too

Please add this option. Very much needed.

I need this as well. Please consider adding this feature.

I need this as well, primarily for compliance and security purposes, e.g. when adding new employees to the team, my clients would like an easy way to monitor email correspondence to make sure that they comply with company's culture, as well as to check if they are sending confidential.

And it would be nice to have "auto CC"
There is also the declined feature here https://plesk.uservoice.com/forums/184549-feature-suggestions/suggestions/35380816-allow-configuration-maybe-via-postfix-to-bcc-all

+1 here too!

+1 For mail groups without sharing the same mailbox

For Mail Archiving / Compliance / Security purposes

Allow configuration (maybe via postfix) to BCC all outgoing mail from one local mailbox to the other one in the same domain?

This is a bad idea. This is beyond the scope of Parallels Plesk. If you want this there are ways to fix this using Postfix configuration as already told in comment.

This should be easily possible with postfix and the 'always_bcc' option globaly for the Server or if you want it more individual by Mailbox 'sender_bcc_maps' and 'recipient_bcc_maps'.

However I'm not sure how this might or might not comply with privacy laws in certain countries.

would be enought to be able to set a default bcc for the accounts

My requirements is to have syndication between different PDAs e.g. you send an email from IPhone and see it in Outlook and Webmail. Therefore regardless of where you send an email from you can see it from anywhere

A "journaling " functionality to use with email archiving service for companies that need compliance with several laws would be great.

In order to minitoring some corporate email, create an option like redirect, to copy every outgoing message from a specific box to another, I had it once and i was very useful for monitoring company emails.