Here is an interesting and informative article on Japanese imported blades to Ming, China:
https://markussesko.com/2013/11/01/j...th-ming-china/
It estimated that over about a century, around 128.000 swords were imported based on official records.
As some of you aware, most of the weapons were destroyed over the last century, especially during the culture revolution period. Even if we can find these Japanese import now they would be extremely rare. However this type of blades are relatively easy to find in China's collector circle. This kind of confirms that these type of blades were mass produced locally as well. We have seen similar shaped blades in China, Korea and Vietnam. Unfortunately it is hard to find official records or studies that distinguish the difference between locally made blade and Japanese imported blade.
I have posted another blade. Please note that this was discovered in GuangXi region, and confirmed is a Chinese made blade. I cannot personally confirm this since it is still in China. It was originally purchased thinking it is a Japanese blade, but then later found it is not.