If you really care about this person as a human, just tell her to do what she can when she has power, and when she’s able to evacuate help her out however you can. I think it’s funny that you seem to be more focused on the work she can do but I’m assuming you do care about her well being first and foremost.
I agree… focussing on her output when she’s enduring a war situation is just heartless. Consider it sick leave. She’s incapacitated by circumstance, behave accordingly.
Currently there are many thousands of people in Ukraine looking for any type of the job. They have chosen to stay or were forced to stay because men cannot leave the country. Some of them are learning programming and coming to job market as engineers. If hiring someone is a way to help and a win-win situation (at lower budget you can offer same netto salary as in Germany), I use this opportunity. There’s only as much as we can do to help, so yes, now, given the circumstances, I focus on making them succeed on the job, because that is the best I can do both for them and for our business.