1. Are historians employed by states or lineages, in a way akin to Chinese official histories, or are they mostly private scholars and researchers?
Private, generally, although they sometimes have the patronage of a court.
2. Are there issues in the history of Cyve that are extremely politicized and controversial?
That depends from state to state and prince to prince- certainly the issue of how an Emperor ought to be selected is very contentious.
3. Will Y2 and future years involve gaining a better understanding of true history, akin to the Dance of Fools Adventure?
I would certainly say yes.
4. are historians generally aware of and free to discuss major gaps in the historical record or knowledge?
Free to discuss, yes- aware of major gaps? Perhaps not as much.
5. Is the law in Elumia codified, or is it based on precedent/common law or a combination?
Common, derived from Imperial Law, primarily.
6. are trials adversarial or inquisitorial?
It depends on where you are, but in the City, they are inquisitorial.
7. Are there trials by ordeal, trials by jury, or trials by compurgation?
Depending on where you are, yes, yes, and yes.
8. Is oath-helping or truth-detecting/anti-lying magic accepted in trials?
Almost always yes, if both parties have access to it.
9. Could a Y1 student face an adult punishment in a court? what about a person of that age?
There isn't a specific distinction made between an adult and a child for serious crimes- so, definitely.