Manshuu Ahen Squad is a story set in the historically largely unrecognized puppet state of Manchukuo. It is a story set in the periods of tense war between China and Japan.
To preface my review, I would like to start by saying that I am Chinese, and I had been to Nanjing's massacre museum during my exchange trip there.
I shouldn't have to prove it, but here are some photos I took there https://imgur.com/a/k95bhHA (there are spots where you're not supposed to take pictures out of respect, but these are the ones I took.)
The first reviewer called this Japanese propaganda and a Nanking denier, but I for one did not feel so.

Manshuu Ahen Squad creates a gripping story showing it's readers the cruelty of war, authority manipulation, and it is certainly not made for the faint of heart. However, the main focus of the story is not about politics (although it may evolve into such as our MC builds up political power) but the survival of a young man and his family.
Higata Isamu is looking to make some money for his sick mother and discovers a way to create opium by chance and intends to sell the drug. The problem is that the Japanese Kwantung Army and the Chinese Green Gang are already selling opium and are already at each other's throat. You could say that they wouldn't be glad to find out someone's trying to break into their market.
Despite only a few chapters available, the manga has showcased its incredible storytelling through art style and writing.

I would say give it a try as it's still a new manga. I could totally see it becoming a dark horse seinen or going downhill into a mess. The choice is yours.