It's not necessary to send a Form 1040-ES voucher when you make estimated tax payments online. If, when you made the payments, you designated them as estimated tax payments for 2019, and gave your Social Security number or ITIN, then it's the same as if you had made the payments with a 1040-ES voucher. The payments will be credited to your 2019 tax.
Enter the total amount that you paid on line 63 of your Form 1040-NR. You do not have to send any documents with the tax return to show that you made the payments.
Please note that a nonresident alien cannot use TurboTax. TurboTax does not support Form 1040-NR.
