Gmail – How to set a profile picture for the Google Groups Email Address in Google Workspace, so recipients can see the profile picture in their Gmail inbox

See additionalemail@gmail.com is an alias for realemail@gmail.com, which implies that addtionalemail@gmail.com is something like: real.e.mail@gmail.com re.alemail@gmail.com or realemail+anything@gmail.com

This is not a separate GMail account and so you cannot receive separate emails for this. You do not have a separate inbox for this. You can create a filter so that the emails sent to the additionalemail go to a particular label.

You can try creating accounts on different sites using additionalemail, you try to subscribe to something using this additional email.

If you go to GMail>Settings>Accounts and Imports you can add additionalemail under the Send Mail as and send e-mails as additionalemail (but the complete header of the sent email would reveal your realemail@gmail.com).

As a bit of a spoiler, we tested this last night. I have two email address (which I will call for the sake of example "test1@gmail.com" and "test2@gmail.com"), and then we did this:

To:      Rebecca <Recip@gmail.com>
From:    My Name <test1@gmail.com>
Subject: this is a test
Body:  blah blah whatever

and additionally

To:      Rebecca <Recip@gmail.com>
From:    My Name <test1@gmail.com>
Subject: this is a test
Body:  this should nest under the other

and voila, they nested. No work required. And then we did this:

To:      Rebecca <Recip@gmail.com>
From:    My Name <test2@gmail.com>
Subject: this is a test
Body:  does this nest with the others?

And it didn't nest!

So in other words, two emails from the same sender with the same subject will nest. Two emails from two different addresses with the same subject will not nest.