Ok... Confusing 
Indeed.
I have physical evidence of japanese Throne of Darkness now. Box, cd label are the same than USA version. But without a peek inside the manual I can't be 100% sure.
But that release date and Capcom publishing name is all over in many japanese websites (also very reliable ones). On selling websites it is priced in yen (almost all USA games sold in Japan without any change from western versions are usually priced in dollars).
Capcom published several western PC games in the Far East, or so it seems.
And in many places is listed as "japanese manual + english game"
Some games were also released in cheap versions, like for example Nox, that we don't have listed as japanese release, that exists in japanese form, in an EA low price software line, with a japan-only box, with japanese writings on it (so it's a real japanese version).