Understanding Aliases, 'Use the following aliases from linked accounts' is always blank?

I have an Alias in my Outlook.com account, and add the same alias in eM Client, but no alias is ever shown in the  ‘Use the following aliases from linked accounts’ field of the Alias form.

When will an alias be shown in the  ‘Use the following aliases from linked accounts’ field?

If its not listed, will it not be used as the ‘Default From/Reply To’?

I want to set an alias email address as my Default Send From/Reply To.  When an IMAP account is added to use as SMPT send only (clunky) it cannot be set as Primary account if the IMAP is disabled, and worst of all the sent items don’t go to the main Sent folder of the primary Outlook.com/ Exchange account.

This setting is for when you have more than one account setup in eM Client. Say you have an account me@mine.com and have alias me1@mine.com setup in eM Client on that. Then you add a separate account me@123.com in eM Client. The me1@mine.com will now be available through the linked account alias option.

Available how?

I have added me1@mine to me@123.com, but it’s not showing up when I look at Aliases under me@mine.com. Am I missing a step or is there a bug?