I'm shutting down one account because I'm moving, but would like to retrain the email addresses by associating them to the account linked to my vacation home. How can this be done?
There is really no need to transfer anything. You can keep using Comcast email accounts even if you cancel service. See here------------------
You can also enable any of the accounts under one by using the mail-fetcher feature in your Inbox page. It's near the bottom of the folders pane----------click on "Add mail account" and follow the prompts. That will also have the effect of keeping you signed into those accounts all the time. Or, you could use a desktop email client like Outlook or Thunderbird to do the same and more.
Unfortunately this Comcast account is owned by another person. I believe they will deactivate the email under their account. Is there a way I can transfer the ownership of the email?
Since you are not the person who started this thread, you need to clarify what your situation is. Are you referring to the primary holder of the account? Are you in the same household? Exactly what is going on?