The Nine Sun Empire
The Chinese characters drawn to symbolize the Nine Sun Royal capital is 九(Jiǔ) - Nine, 阳(yáng) - Yang.
Stolen from Royal Road, this story should be reported if encountered on Amazon.
The character 阳 can refer to quite a few things, in this case, it refers to the sun, as the Chinese characters for the Sun are 太(Tài) - Extreme, 阳(yáng) - Yang, which directly translates to 'Extreme Yang' which is what the ancient Chinese viewed the sun as, an object of extreme Yang.
The Chinese characters drawn to symbolize the Radiant Sea academy is 曨(Lóng) - radiant/lucent, 海(Hǎi) - sea
(Author's note 1, 30/07/2020) Hi, this is um, the new version of the map I'll be using, I erased all the maps except for one, and this map is still pretty blank, but bear with me, I'm trying to start a bit slower and I'll be adding things in as I go.