Happy to help.
That's a good question. Real ninjacraft required here....
Here's my best guess at this one. It's probably not the perfect solution, it's a workaround, but should work if you're careful about what address pops up when you hit reply.
So, Follow my guidance above for creating your IMAP account. Except what you're going to do is create a separate IMAP account for each alias.
So.....Account/alias 1
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Create a new email account 'other'.
For the following fields enter
Name: Me
Email address: me@me.com
Complete all other fields as per the above post, remembering to use your actual iCloud name for the login, actualme@me.com
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Onto account/alias 2
================
Create a new email account 'other'.
For the following fields enter
Name: Someoneelse
Email address: Someoneelse@me.com
Complete all other fields as per the above post, remembering to use your actual iCloud name for the login, actualme@me.com
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And so on.......
So now when you send email from your different aliases, you'll have a different name identified with each alias as you would normally through iCloud. You're just doing it manually rather than using the server version.
The one problem with this method is that it will download two copies of your mail as you've technically set up two duplicates of your email inbox.
To mitigate you can do two things
First: In Mail, on ios, don't use 'all inboxes'. If you do you will see duplicates for each IMAP box that is added
To correct this, Select one of your aliases as the inbox that you work in. It should receive all mail sent to any of your aliases so you'll still see all mail.
Second: go into settings, select mail and select the 'Fetch New Data' option. Now tap advanced.
For the primary inbox you selected just above, set it to 'Push' or 'Fetch'. Leave your contacts, calendars as push as well.
For the others, set them to 'Manual'.
This will reduce the amount of data you download and, for most of the time, ensure that only one of your IMAPs is downloading all your new mail......as opposed to all the IMAP inboxes downloading duplicates
Phew.
Hope that helps.