Hmm ... I could swear I once read an interview with a private military & modelling enthusiast in a Chinese magazine who even described how he made them.
Unfortunately the original link is dead and so is the link to the original site gone.
I can only tell you what results I was able to find.
I first used keyword search, and all the results pointed to links from various self-media outlets. These self-media outlets have no credibility, and their articles are complete nonsense, with most articles lacking even the most basic military knowledge.
I then used an image search engine. The results are as follows:

After removing irrelevant information, my analysis yielded the following points:
1. All photos are from the same scene. Most of the images are processed versions of the same original photo. After analysis, there are approximately 2-3 actual original photos (taken from different angles).
2. The background in the photos is a small conference room. Based on its decor style, it matches the typical decor style of a small conference room in a state-owned enterprise. No individual would use this style of decoration in their private setting.
3. There is an LED screen above the projection screen in the background. Some photos show that the screen displays bilingual slogans in both Chinese and English.
The above characteristics indicate that the original source of these photos likely came from a small meeting of a Chinese state-owned enterprise (with foreign participants). It does not fit the characteristics of a private event.
I am only providing an analysis of this specific photograph and will not comment on any other situations.
@Michael , Can you please translate the Chinese text in the bottom right please.
View attachment 160767
This text is simply a watermark on the image.
The watermark indicates that the content was published on Tencent's self-media platform"企鹅号" by an author with the ID "兵器次元".
This is worthless.
The information I could find indicates that this photo originally came from Super Base Camp (cjdby.net), a very famous early Chinese military forum. However, that website is now closed, making it impossible to trace further information.