I dimly remember a story about a wrong number phone call connecting a man with a woman in an alternate universe where the Japanese won WWII. Unfortunately both my memory and my Google-fu are failing me on identifying the source.
A wild guess but "The Man in the High Castle"? I could be wrong, because the phone call doesn't happen in the novel by Philip K. Dick that the Netflix show is based on and I haven't watched the show. However, the premise is alternate history of Japanese winning WWII.
In the story I remember, the parallel universe is discovered when they agree to meet at an important landmark building in New York - but they never meet, because in her universe the original building was destroyed by a bomb that hit New York and the building was rebuilt in a new location.