If your joint AGI, excluding your unemployment income, is less than $150,000, you will almost certainly be better off filing jointly, as gloriah5200 has described. However, for 2020 only, if your joint AGI, excluding your unemployment income, is $150,000 or more, there is a possibility that filing separately will work out better if it allows you to claim the $10,200 unemployment exclusion. That would only be possible if your AGI, excluding your unemployment income, on your separate return is less than $150,000. The only way to be sure which way is better is to prepare tax returns both ways and see which way works out better overall. Be sure to take into consideration state taxes as well as federal.
Doing the comparison with TurboTax Online is difficult and clumsy. If your income is in the range where filing separately might be advantageous, you should consider using the CD/Download TurboTax software instead of TurboTax Online.
One point that gloriah5200 mentioned is worth emphasizing. If you file as married filing separately, essentially you must either both itemize deductions or both use the standard deduction. You cannot have one of you itemize and the other claim the standard deduction.
