The capital hasn't been moved to Tokyo yet.
You think this is what the star in Oosaka means? That got me confused and if it means to mark the capital it feels really wrong to me. For starters, Oosaka itself wasn't the capital, I guess Kyoto and Oosaka are too close together so it is better for the game to consider as a single city? But if so it should be named Kyoto, because that is the name of the capital. Oosaka is bigger, but Kyoto is the capital, so that feels more important to me to carry the name.
More importantly, though, if this is pre-Meiji Kyoto wasn't the capital, not
really. In practice, during the Edo era (1603-1867) the capital was Edo (Tokyo) which gives the era its name. It is where the Shogun, the de facto leader of Japan, resided and where the political power resided. The role of Kyoto as the imperial capital is mostly ceremonial and it doesn't feel accurate for the game's purpose to be set as the capital. The moving of the capital should be an event that change Edo's name to Tokyo but it shouldn't be an actual change in political set up (the government change, of course, but not the capital move itself). The reason the imperial capital changed when the Emperor rose to power was precisely because it was there the political power had been for almost 3 centuries. On a similar note, I find dubious the idea of using the Imperial symbol for the flag, the Tokugawa emblem or even the regular Japanese flag would be better for Shogunate Japan.
All in all that screenshot made me concerned they will portray Japan as if it is governed by the Emperor from Kyoto at the game start. If I am not mistaken Vic2 had no way to represent the situation and even EU4 kinda railroads the event to unite Japan as the "Emperor", which is not very accurate for the time period. On game start Japan should be governed from Edo by the Shogun, not the Emperor in Kyoto. Of course, since this screenshot is not of game start maybe this is just a Japan who took a different path to Imperial rule, never moving to Tokyo, so that is fine. I still argue the capital should probably still be Kyoto, though, if the Emperor never bothered moving to Edo would he really move to Oosaka instead? It is so close to Kyoto already that keeping the historical capital seem to make more sense to me.