How to change cost basis? Stocks inherited Nov 2019, transferred to Vanguard March 2020 sold later in the year. Vanguard's cost basis does not reflect inherited cost.

Simple ... edit the sale in the program to make the correction. 

There are checkboxes in the screen following the entry of the sale of an individual security; one to adjust the cost basis and another to adjust the holding period.

Ensure that you also check the holding period box (if you held the stock for one year or less) since the holding period for the stock should be long-term if it was inherited (regardless of how long it was actually held by you).