Customise New York time lapse watch face - actual location day/night transitions

This is my watch face, the New York time lapse. You can see the time where I live (Sydney, Australia) is 11:29pm on Monday 18th September (Sydney is +14 hours ahead of NY). Up top I have a NYC world clock complication. I want to make the selected time lapse image show the true day/night transitions according to selected location and not current GPS location time.

Called Apple, guy said it default bases location transitions off GPS location time and not theme location. Couldn't find a way to further customise it.

Anyone know how this could be done?

Thanks 😀