If you have specific evidence of Chekhov referencing Confucius (the similarities are so striking that either he came up with them independently, which was my original point, or he was inspired by Confucius, which should then leave traces) please do tell! That would be really cool.
But I'm not even a hobby historian or philologist, more of an armchair philosopher.
Which Russian missionaries translated which Chinese classics, since that you've already searched? I'm turning up Russian -> Chinese, not the other way around.
Hopefully this link works for you and isn't dependent on local cookies or something. But the book is: China and Japan in the Russian Imagination, 1685-1922: To the Ends of the Orient By Susanna Soojung Lim
https://books.google.com/books?id=RQldRM5wlfcC&pg=PA65&lpg=P...
Russia and China were bumping into each other before Chekhov's time, and a bit of Googling is turning up cases of Russian missionaries translating Chinese works to Russian in the early 1800s.