MAC Outlook can't change display name imap in new version

I am having the same problem right now, cannot change my full name >.<

It's 2022 and still not yet solve?

I was also able to get around this by choosing the "Not IMAP?" link in the top right (even though it is definitely IMAP).

From there I was able to bypass using the Microsoft Cloud option and just enter my IMAP server connection settings as I was before, and after that was done I was able to change my name to my actual name instead of just my email address or the label that Outlook had chosen for me to use. I appreciate your guidance as that put me in the right direction.

OMG THANK YOU. I was searching high and low for hours today for a fix to this, and I was just about to ditch the threads until I read this. I am beyond grateful - it's all working now.

Thanks again!

That's right.

However, I have discovered an additional problem which is a deal-breaker for me. In New Outlook, I could not add folders to my email accounts, or Gmail accounts at the very least (the option to add folders was greyed out). In order to add a new folder, I had to revert back to Legacy Outlook. But even then, when I moved emails into a folder, most of those moved emails would not reliably appear in the folder; sometimes, some of the emails would appear when I clicked to display folder contents, but most times, a folder would only display one email, when, in fact, that folder should have been displaying about ten emails. I found this problem was only present on the desktop, and not mobile. But of course, this is a huge problem. And for that reason, I have permanently shifted to using the Mac OS and iOS Mail app. It allows me to easily edit my email accounts' sender name(s), allows me to easily set-up and reliably use folders to organize my messages, and... I am finding that it performs much faster than Outlook.
Goodbye Outlook. And, don't be surprised if I cancel my Office 365 subscription before it renews.

From my perspective, it appears that the root of the problem is "Microsoft Cloud". If you don't sync your email accounts with Microsoft Cloud, and instead sync directly with IMAP, you will be able to edit the first and last name of the "sender" of your email accounts. Just like we were able to do in the 90s.

Agreed, this is the issue. Clever workaround! And yet another problem in New Outlook is that it won't add an IMAP account without Microsoft Cloud unless, you specify SSL for incoming server, and, not at all obviously, StartTLS for outgoing. That's not required in Legacy Outlook; you can just specify SSL for both and call it a day, as you discovered.

So, there are two super basic problems with New Outlook (inability to change name when using Microsoft Cloud, and inability to add an IMAP account in a straightforward fashion without it).