Relating to this video:
In short, the world of Valerian is one in which the docking of the Soyuz and the Apollo heralded a new era of international cooperation rather than a further twenty years of Cold War. A large international co-project was evidently announced and the Alpha Space station was built in Earth orbit by the Russians and the Americans.
What happened in 1998, at Alpha Space Station in orbit around the blue-green world, was not merely two nations meeting. When the European Hermes spaceplane, proposed in the same year as that first historic handshake, arrived to dock at Alpha, it represented a coalition of nations. Space was no longer the province of a few tiny humans, but was rapidly evolving to belong to humanity.
The space station grew as time went by. In the year 2019, China’s massive Tiangong-3 spaceship was warmly welcomed when it came to take its place at Alpha. The captain of the Alpha Space Station, one thirty-year-old James Crowford, enthusiastically greeted his Chinese counterpart Wuang Hu, who himself could not seem to stop smiling. Later historians would mark this moment as the end of international tension, and the beginning of what was the first Great Age of human cooperation.
Besson: [Laughs.] No, no. It was very, very important and it was an idea that I had for a long time. I wanted to start with some footage from 1972. I want to start from who we are, okay? In 1972, Americans and Russians are able to smile to each other and shake their hands. And we forgot! It starts well. ...
But it’s very important to show that these humans, no matter where they come from… okay, here is Russia and America, but they’re so happy to meet! They’re so happy to shake their hands. And then after we see the Chinese and they’re happy too.
So, we have the Americans, the Russians, the Chinese, the Europeans, and various humans from different regions or countries, which I could summarily guess are intended to represent some South Asian country or the region (India?), some Middle Eastern country or the region, some African country or the region, South America? (flag looks like Argentina/Uruguay?), some other Asian country (Mongola?). But I'm not confident on all of them.