Unlikely? I'm not surprised at this. It took someone long enough to realize the potential for a Touhou/Ranma 1/2 crossover.

Well, theres already a Ranma 1/2 Touhou Opening. Really, what anime opening as Touhou NOT done? Even if it is a little choppy. Meirin was playing Ranma in it.

Wonderin' who would be Happosai~

Yukari. No contest.

Nah, Mima would be a better Happosai. Yukari would be Cologne. Now who would Yuuka become... Herb?

Nah, Eirin is Cologne. The Chinese cast = Eientei.

Wait, then who at Eientei would go yandere over Meiling ?

Reisen.

Better question: Who are the Kunos?

Cirno, Daiyousei and Letty ?

That's the thing about Rumiko-sensei's works, they're full of diverse and interesting characters.

Who would become the first and best Tsundere of all time, Akane?

My choices:
Tewi as Nabiki.
Kaguya as Kodachi.
Eirin as Dr. Tofu.
Wriggle as Konatsu.
Mokou as Saffron.
Alice as Gosunkugi.
Yuuka as Herb.
Marisa as Azusa.
Meiling as Shampoo.