High fantasy

Major plot spoilers ahead!
The name 'Arkadia' is misleading. Arkadia is not the universe, or the planet or even the title. Arkadia is the kingdom. or rather, both of them. The story, beginning with 'Of Stars and Gentle Deaths', takes place on two seperate worlds, mirrors of each other and existing simultaneously. They are called Istuvia and Khantis, and they both have a kingdom of Arkadia both of which are very similar, yet different. For example, Istuvia has the Black Magi, and order of magic users consisting entirely of women garbed in black. Khantis, however, has the White Magi, a similar order composed entirely of men, garbed in white.
These two worlds are both looked over by the same gods however. There are thirteen of them: Talnai, Liliaeth, Filorin, Neiha, Fyrdiese, Tylus, Myvekim, Roni, Myria, Tukos, Viathyrda, Kagnus, and Siatha. They exist in a space in between the two worlds. Once human, their godhood came from their residence in this place. Just as a persons actions influence the world around them, it influences this space as well. However, since a persons influence on the world is almost completely insignificant compared to the size of their world, their effect on the in-between place is almost unnoticeable. But compared to in between world, the gods are significantly larger, and thus, their influence over the two worlds is much greater, to the point where it is reasonable to call them gods.
The story of Arkadia revolves around two girls: Eloise and Viratheya. Both are unique in that they exist in both worlds. Eloise is awake and lives in Istuvia, she has a body that is sleeping in the catacombs beneath the royal palace in Khantis. Similarly, whilst she has lived her entire life in Khantis, Vira has a body beneath the palace in Istuvia. Neither of the girls know this, however. In fact, no one on either world knows of the existence of the other. The story begins when Vira and Eloise begin to have shared dreams, in which they can speak to each other, but they naturally assume they they live in the same world, seeing as they both live in a city called Kydestra in the kingdom of Arkadian.

there are many different types of magic, from priests to mages to witches and artificers,

mostly medieval, with some magical devices floating around, especially in Elosthera and Kydestra.