@swinokur001
...Opinion: Still, I don't recommend you do that this year. With all the errors on the stimulus payments, and the resulting changes that the IRS makes administratively after they get your tax file.....who really knows what your supposed refund will actually be...could lead to a lot of confusion next year as to what the exact amount of your refund really was that was "applied" to 2021 taxes.
Just get your refund in the normal fashion (D.Deposit or check) , and use the IRS DirectPay website to make an exact payment amount for the first Qtr 2021 estimated tax payment (by 15 April):
https://www.irs.gov/payments/direct-pay