Using Classic Outlook on Windows for personal email, calendar, and contact management
If you're desperate to make it work for the time being, I found that modifying the name of the folder to include a number at the beginning of the name seems to sort it in numerical order. If it doesn't work initially, I found that moving the folder you just renamed into another folder and then moving it back to the main area "resets" it and allows it to sort by the number you just added.
Microsoft, please fix this! I'm excited to work with the new outlook, but I need to be able to control my folders.
Thank you for the proper work around