Is there a way to add an Outlook additional mailbox store?

I am trying to create a script that will recreate the outlook profile. Currently I am looking for a way to add additional mailboxes via the Outlook com object, since not all mailboxes can be added via automapping.

Unfortunately I have not found an approach on the internet. Is there any solution at all?

Outlook Object Model does not expose that functionality. You can either use Extended MAPI (C++ or Delphi) to add a properly configured instance of the "EMSDelegate" MAPI service, or use Redemption (any language, I am its author) - it exposes RDOSession.Stores.AddDelegateExchangeMailBoxStore method.