Thanks for reaching out to the Microsoft Q&A forum.
Based on my testing and research, I’d like to share some insights regarding how folder sort order works in Outlook for Android.
If you select View > Folder pane > Sort folders > Order folders A to Z in Outlook on the web, this setting will not sync to Outlook on Android.
However, if you choose Custom folder order, any changes you make in Outlook on the web will sync to the Android app. This behavior is also mentioned in the Microsoft Support article: Why have the order of my folders changed? - Microsoft Support
Additionally, Outlook for Android currently does not support manually ordering folders within the app. Features such as creating, deleting, renaming, and moving folders are still rolling out, as noted in the Microsoft 365 Roadmap: https://www.microsoft.com/en/microsoft-365/roadmap?id=489831
In conclusion, if you want your folders to appear below the Inbox in alphabetical order, the best option for now is to set the sort order to Custom folder order in Outlook on the web and manually arrange each folder there. These changes will then sync to Outlook for Android, as the ability to manage folder order directly in the Android app has not been launched yet.
I hope this provides additional clarity. If you have any updates or further insights, please feel free to share.
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