Managing personal Outlook.com account settings, security, and privacy
@Peter Gillespie said
list of emails that use my primary account as it's recovery email
You can get a masked list (similar to what EA is showing you) using the forgotten username lookup:
https://support.microsoft.com/en-us/accounts-billing/manage/forgotten-your-microsoft-account-username
If you ever signed-in to the account on a Windows PC, there might be some clues in the the Windows Credentials Manager
https://support.microsoft.com/en-us/windows/security/credential-manager-in-windows e.g.