You actually can make manually entries in any TurboTax desktop (installed) product and still e-file. The software will generally not allow you to e-file if you make overrides. The impact of manual entries is limited to voiding the TurboTax accuracy guarantee.
Regarding the form in question, I have yet to find any consumer-level software company that has indicated whether or not they plan to include Form 8997 for the 2019 tax year. We can hope that will be the case but, at this point in time, the form is still in draft mode and we will have to wait until the IRS finalizes the form.
