For anyone who does not wish to go the Outlook route, Thunderbird is an excellent email client and accessible.
For the adventurous and those who already use and like any Chromium-based browser, the Vivaldi browser has just released a version that has an integrated email client (yes, email client, not webmail) as a feature of the browser. It's almost certain to be accessible given that the whole of Vivaldi is driven by underlying Chromium presentation management code. Since there are a lot of folks who are using Edge, Chrome, Brave, etc., this would be an experiment worth trying. And the fact that Vivaldi has a privacy-centric ethos is a bonus.
Brian - Windows 10, 64-Bit, Version 21H1, Build 19043
It is better to be hated for what you are than to be loved for what you are not.
~ André Gide