TurboTax being geared to citizens/residents and resident for tax purposes ( and filing form 1040 ) I do not believe it will be able to handle a W-2 with no FICA entered -- it will show this as an error.
How did you file last year --- as resident aliens ( on form 1040 ) or Non-resident aliens on form 1040-NR ?
Assuming that you were both Resident Aliens for 2018, if you enter her W-2 as is and when it talks about Social Security and Medicare due, it should be asking if your spouse was a medical resident -- say yes to that . This will allow the software to be happy without charging you for FICA taxes.
