Using Classic Outlook on Windows for personal email, calendar, and contact management
@Trevor Williams said
I still need to access my old sent reference emails from Outlook
You should be able to access your Outlook email from any browser opened to https://outlook.cloud.microsoft/ If this doesn't work, please advise and we'll work on another approach.
I would also suggest you setup Auto Forwarding to your GMail account so that any mail sent to your Outlook address follows you to GMail.
See the "Outlook.com" tab at
https://support.microsoft.com/en-us/outlook/mail/turn-automatic-forwarding-on-or-off-in-outlook