Lets move WordPress Mail Authentication from Basic to Microsoft Graph , Choosing one of an available plugin which supports Microsoft Graph . Search , Install and Activate , Search for “Mail Integration for Office 365”
Login to Azure Portal and register an Application
From Plugin Settings get the redirect URI and apply above
Create a Secret valid for 3 years from Certificates and Secrets
Emails are sent out using Microsoft OAuth / Microsoft Graph. You should feel proud every time you kill basic authentication .