It should be no problem to configure generic emails. Try configuring the Email Account as follows:
- Email Address: “sales@example.com”
- Connected User: “system-manager@example.com”
- Make sure you’re logged out from microsoft with your personal account
- Click “Authorize API Access” and log into microsoft as sales@example.com
Once the Email Account is authenticated, you can grant any user access to this email account via their User DocType.