I've been trying to ID this coin which I thought was Japanese, but I couldn't find a match. I did a Google image search and the top match is a Wikipedia page for a Chinese coin called a Yongle Tongbao from the early 1400s. https://en.wikipedia.org/wiki/Yongle_Tongbao However, another match goes a Numista page for a Japanese 1 mon from 1587-1608. https://en.numista.com/221649 Both coins pictured look identical to me. So which is it?
Well, they're both right. This design (Yong Le Tong Bao) was first issued in Ming China. It was later copied in Japan (read in Japanese as Ei Raku Tsu Ho) from the 15th- 17th centuries. The Japanese versions seem to be scarcer than the original Chinese. As for telling the two apart... that's above my pay grade.
Both are correct. Did you read the wikipedia article, or just look at the picture? The coin started as a Chinese design. But the Japanese were trading with the Chinese. So they started making the same coin with the same design. I don't know how to tell the difference between the two, but the articles you linked clearly state that original Chinese pieces were made for trade, and Japanese pieces were made to imitate.
You got me. I just skimmed the beginning of the Wikipedia page as I was checking other sites to see if they agreed.