Port Arthur) would roughly fit the screenshot in terms of rivers and mountains, so it could be that I guess. While it doesn't fit any of the myriad romanizations of Mandarin, it's a reasonable approximation of (Hanyu pinyin) 'Nouyou', which is weird but theoretically possible in Mandarin. And 'Noyou' sounds more Chinese than Russian to me.

But I can't match the screenshot's river to anything in Vladivostok. If that's geographically literal, it can only mean the Russian Far East, which in turn would surely mean Vladivostok and Golden Horn Bay. *Noyou Port* is supposed to be further north than Hanami. I wonder if the map will stretch as far as Mount Fuji? Planes flying past the mountain would generate great screenshots. 'Hanami' is also valid Mandarin, but it would be a weird Mandarin name. But neither the river nor the peninsula (the Dangjin area) match the screenshot. Incheon (Korea) also has a famous airport in a bay and 'Hanami' is valid Korean too. Even the artificial islands don't line up with the screenshot today, but maybe they did in the past. Tokyo Bay has the Bōsō Peninsula in the right place in relation to the rivers, but only has one natural island. Osaka Bay is most famous for hosting an airport (on an artificial island), but the screenshot shows a peninsula, so that doesn't match. But these maps are supposed to be flat and Japan famously has very little flat land, which suggests either Kansai or Kantō.

*Hanami Bay* is temperate and sounds very Japanese.

Singapore is created by such a channel, and has a famous airport, but it isn't best known for its beaches (though it has some nice ones!), especially on the northwest coast. The distinctive feature of the screenshot is the channel that runs from sea to sea creating the island in the right. But that covers a huge portion of the world. *Asanu Beach* is tropical and the name sounds vaguely Malayo-Polynesian. C:S maps are usually 'inspired' by real places, aren't they? Any guesses as to where these places are?

Airport cities skylines