The ability to freeze a header row or column would be a huge help in formatting information! Without it, editing tables and finding the information we need has been difficult and error-prone. 

You mention here that you can embed a google sheet as a work-around, but in my experience the formatting does not carry through and the row does not stay frozen when embedded. 

Thanks! 

This would be such a huge help , as mentioned in some other replies embedding the excel/sheets does not carry over nicely. Being able to freeze columns both vertical and horizontal would make navigating large spreadsheets easier for teams