**Tax Year 2018 or earlier** How to enter the alimony deduction if I have a foreign ex-spouse without an SSN or ITIN?

I saw a couple questions on here about getting the alimony tax credit while having an ex-spouse who is a foreigner. I am sort of clueless on what exactly I need to do in the SSN box when the foreign ex-spouse has no SSN or ITIN.

Some have said that the ex-spouse has to get the ITIN. But, if they are living in a foreign country why would they do that? There is actually no point because it's an extra headache to do that - especially if there is no intrinsic benefit.

So the question is, what can I do if I've sent them the W8? Can I still use turbotax and enter nothing in the SSN or does this have to be manually done and I have to send in a W8?