After you file

Without a 1099-B,
IRS requires details of your SELL transactions to be supplied on some Form 8949,
or on your other forms (e.g. consolidated 1099-B or spreadsheet) which have the same information and in the same manner as Form 8949.

 

Details include description and  "Date Sold".

If you're playing games with your basis, that's not nice.

@rynstrss