Rabban Bar Sauma is, in a way, the Asian counterpart to Polo. He was a Uyghur Nestorian Christian who went from Yuan China on a pilgrimage to Jerusalem that he never completed. Afterward, though, he was made a diplomat of sorts for the Ilkhanate and traveled to Europe, apparently meeting "the King of Byzantium, the Pope of Rome, the King of France, and Edward I, King of England."

There were some other people from Mongol China who would go to Europe, but Sauma appears to be among the most notable.

I've taken this information from a translation of a Syriac history of his and other Nestorian Christians' travels available online here.

Also u/The_Manchurian has an even more detailed answer on Sauma here.