I know there were some interesting one off interactions or explorations like Gan Ying but I was shocked to read a reference to the Roman Embassy in Daqin in the late 100’s.
Did the average person in either empire have a common knowledge of the other culture or was this knowledge more likely limited to explorers, intrepid merchants, and the ruling class?
Even scholars and explorers didn't really know anything about the other side since they never went there in person. They relied on reports from intermediary merchants but there were probably several steps between them. Here are some previous answers by u/Dongzhou3kingdoms: