E-filing for tax year 2019 has already closed. You have done your part by mailing in your amended return. Now you would just wait until it has been processed. If the IRS hasn't processed your 2019 amended return by the time your tax return for 2020 is processed, the carryover will likely not be factored in (as the IRS will not have record of it).
If it is not included, you can file an amendment for your 2020 taxes after your submitted return has been processed by the IRS. See this FAQ on How to amend a return.
