Could we get a peek at Tien Cosmology. I am building a Tien flavored race and need to come up with a creation myth for the race. Is Ten cosmology more Japenese based or chinese based?
Saying "Tien" on Golarion is like saying "Asian" on Earth. So, the answer to your question is yes to both cultures, but there is more to it as there are more cultures than two in Tian Xia. The Dragon Gazetteer should have what you are looking for if I am not mistaken in my reading of the product description and what the designers and developers at Paizo have been saying. It comes out in December. Hopefully, we will see previews before it comes out. I do know that it is supposed to have the pantheon of deities worshiped in Tian Xia, including new gods. It will also have racial information on all of the main races that inhabit Tian Xia. If you are lucky, that part will contain what you are looking for.
I doubt that being on the other side of the planet will alter the planar structure of the multiverse. That being said, the Tien (either as a whole or varying some by specific culture) likely have different interpretations of people and places in the Great Beyond, and mayhaps some "expansions" to the plains to contain some Asian-themed deities or planar realms. Which is a fascinating idea and I hope Todd has worked at least a little bit of that information into the Dragon Empires Gazetteer.