It appears it can be done in Outlook. If you go to Control Panel -> Mail you should be able to follow these steps for Windows Mail also. There are a couple of different websites to see the steps:
https://businesstechplanet.com/how-to-add-a-delegate-to-your-inbox-in-outlook/
https://support.microsoft.com/en-us/office/manage-another-person-s-mail-and-calendar-items-afb79d6b-2967-43b9-a944-a6b953190af5
https://csuf.screenstepslive.com/m/47716/l/492007-add-an-additional-mailbox-in-outlook-as-a-delegate
--If the reply is helpful, please Upvote and Accept it as an answer--