ooh. This is a strange one.
IANAL but I suppose the terms of service would be the thing to look at here. I don't see anything explicitly talking about transferring an account but
Subscriber is solely responsible for any use of or action taken under
Subscriber’s password and accepts full responsibility for all activity
conducted through Subscriber’s ...
You login into Super User (and by extension the wider Stack Exchange network) via 3rd party authorisation tools
Your Super User account is linked to other accounts you may have on the network.
This sounds like a really bad idea.
You have no way of disassociating your Super User account from the rest of your accounts. So if you handed over this ...
You can request email notifications for your inbox, if you haven't accessed it in a while, which takes care of answers to your own questions, and comments to your posts or addressing you.
While you can mark questions as favorites by clicking the star, and have them show up in your user profile, there's no email notifications for it.
There's also an RSS ...
You don't get emails by default, unless you've specifically enabled that when you ask a question.
For comments & other notifications, you can click on email settings and enable the email notifications for your unread notifications.
But I can’t see in logged in user account in “Edit Profile & Settings”
and “My Logins” and ”add more logins…” an option to add email. There
are only more Facebook, Google+ like options.
If you click on the “add more logins…” then the way you could create an email only account is to simply create a Stack Exchange account which would be a local system ...
As of March 2020, you can follow somebody else's question and be notified of any new answers; you will also be notified for edits to and comments on the question though. You can combine that with the setting to receive emails for unread notifications, as @DanielBeck suggested.
There is also an RSS feed for a single question which can be found in the right ...
Can I get it back? And how?
Usually you'd go to the forgotten password page. If you tried all e-mail addresses and still can't log in, please contact the Stack Exchange team directly.
Can I possible by any chance ask for this user (me) registered email address?
For privacy reasons we cannot hand out this information, sorry.