Should hordes be Tengri?

[Wizzington]

East Asian hordes are Tengri, Central Asian hordes are Muslim.

 

[Wizzington]

Gameplay justification, to let them use the new mechanics.

 

[Trin Tragula]

golia, Oirats and Buryatia are properly Tengriist, while Sarig Yogir is accurately buddhist.
Tengriist manchus are a bit of an issue, they were shamanist until turning to "chinese folk religion" a.k.a Confucian in the game (I assume) when they became rulers of China. In my opinion, they should start as Shamanists and switch to confucian when forming Qing.

Tengri is now a stand in for all sorts of East Asian Shamanism. That's why the Tengri area was expanded.
Mechanically I think you'll find it works out pretty well with the Manchus mixing their Shamanism (Tengri in the game) and Confucianism.
In other words what Wiz said.