We need an Eastern themed caster

[Iscah]

Kyokuho himself in Hingan, but the geomancy he practices is closer to the original since it's legitimate magic. What the charlatans are doing seems to be how the art is perceived as a whole in Hingashi.

You're making assumptions that don't seem to be there. The quest says that people started doing the false type of geomancy after seeing Kazan do it for real. The false type is rife now in Hingashi (or at least Kugane) as a consequence, but that isn't the same as saying the false type is inherently Hingan or the true type is Doman.