After trying to make heads and tails of the descriptions offered by the game:
https://pillarsofeternity.gamepedia.com/User:Tagaziel/worldrefs
And hoping that I managed to track most of them down, I decided to put together a rough map of what Eora might look like:
https://drive.google.com/file/d/1p41sNv3S-GBOoymbjdekaSGz_Ddb_KC-/view?usp=sharing
Of course, I had to work with limited sources, mostly in-game mentions, but also posts by JES and other developers. The basic assumptions are as follows:
1. As JES said, the Living Lands and Rauatai are northern hemisphere, with everything else in the south.
2. Aedyr is on the equator, which is about as close to a definite location as we get. The location of the Reach is extrapolated from the mostly temperate climate together with Ixamitl's savanna's, the mention of Old Vailians sailing into the Deadfire past the reach, and the logical landing spots of ships from the colonial powers.
3. Deadfire is plotted according to in-game coordinates. The entire map is based on that, in fact.
Comments and feedback are welcome. Yes, Yezuha is kind of Australia, what with it having red deserts and being dry as ****. No, I'm not sure the size of the eastern continent is accurate. Yes, I have too much time on my hands.