Using New Outlook on Windows for professional communication and productivity
@Winter, Kaye said
I'm trying to edit the column headers in the inbox of New Outlook that allow you to sort messages
In New Outlook for Windows or Outlook Web you can still click or right-click on a visible Column Header to sort by that column.
For columns that are not visible, use the Sort Control in the upper right corner.
Unlike Classic Outlook, in New Outlook the number, type, and position of the columns is pretty much fixed. If you want more flexibility in your Inbox View, all I can suggest is that you Vote for and Comment on these Feature Request:
New Outlook - Needs More Flexibility to Add Columns!
https://feedbackportal.microsoft.com/feedback/idea/4f693d1c-fa2c-f011-9d48-7c1e52ead3c1
Please add back the ability to add columns to inbox. Specifically the "to" column
https://feedbackportal.microsoft.com/feedback/idea/8935287a-4762-f011-95f2-7c1e52a55eeb



If the column that you want is not in the Available columns list, click the Select available columns from box to see additional sets of columns. To create a custom column, click New Column, enter a Name for the column, and then click the Type and Format of information that you want the column to display. To remove a column, in the Show these columns in this order list, click a column name, and then click Remove.