Just enter the total proceeds and cost basis for each type of sale (Covered Short Term, Covered Long Term, Noncovered Short Term, Noncovered Long Term, enter a final sales date of 12/31/20, manually adjust the holding period to reflect S or L, and you can enter the cumulative wash sales for each type of sale.  Every 1099 form will have this information in summary format.

The IRS doesn't care if you put down 12/31/20 as a fake sales date as long as you correctly capture the short term or long term nature of the sale.