There's some elements in game art I've picked up on but do not know words on and I'd like it if someone could name them for me.
I would like to agree with Ekko here, animation-wise the way he holds his bat can pass off as a sword(as shown in sandstorm) plus his kit is a good canvas for the very oriental and magical VFX in this new skinline.
Ditto for Katarina in where she would be a good idea, only small problem is the Warring Kingdom being there already, although that can be pushed through provided it's unique enough, like how they made each of Taric's old skins look different enough, despite being gem themes, and still look very unique in their own rights.
What I have to argue against however, is Ahri (putting her skin release frequency aside) and Leblanc. Skins have a stronger impact thematically if boundaries are pushed provided it's execution is done well, which was the case for Janna. But there are still sme boundaries that cannot be pushed, otherwise it will actually reverse the impact, imo. Ahri does not have space in her kit to have large, "rectangular" swords. Everything about her combat elements kit is spherical; orb, bulbous heart, fireballs. As such, swords, having their height significantly larger than their length (vertically) would look very unnatural on Ahri.
Leblanc has a staff, like Janna, and could somehow work like Janna's skin if executed well. However, Pushing the same boundaries for two characters is a bland move to Leblanc, and "kills" one of the charms in Janna's skin; an element unique to the combination of Champion to skin that makes the skin itself more desirable than the others.
Project and Star Guardian skins are a good representation of "charms"
As for Draven, Sejuani and Shyvana, I'm interested in seeing how oriental skins would turn out for them, but I feel the swords set would not work for their "boundaries" If they, along with Leblanc and other champions were to be put in an oriental style skin, I'd say they're better off in another/different skinline/name that focuses on a different element, after all, It can be under the same umbrella of [Immortal Journey]
(also ancient civilisations didn't only have swords, they had other weapons too, which is more leeway for more skin lines)