We are getting closer, and are still working thru some bugs, but hope to release this as part of a Public Preview pack in early 2021! (Windows 10 released with the December 2020 pack this week)
You can learn more about the new Microsoft Teams Public Preview program here: https://aka.ms/TeamsPublicPreview, and Teams administrators can find documentation to manage which users will see the Public Preview option here: https://aka.ms/TeamsPublicPreviewAdmin
Thank you for your feedback. The team is currently planning for a profile editing experience for Guests that will include changing profile images as well as updating display names. We will share an update as soon as one is available.
An error occurred while saving the commentAnonymous commented
Changing Display Names for guests in Azure portal will successfully update them across all the various admin portals for Teams and Office 365, but doesn't update in the Teams app even after quitting the app, logging out and in again, etc.
If this is only changed for Admins to see, then I don't really see the point of being able to update guest user info at all.