Debatable? Not really. It as scripted, directed, composed, animated and produced by the Japanese. However, it is true that the original language is English, but this is was partially because of the fact all the Resident Evil games were released in Japan with English audio. However, there was a Japanese dub produced for this.
In any case, it's important to look at the entire staff listing whenever making a topic whenever you're unsure. Resident Evil itself is a Japanese property, and unlike the Live Action movies, this was for the most part done entirely in Japan, with the exception of the crew going to the United States to record the voice acting for it.
Also, this doesn't reach "Direct to Video" or "Original Video Animation" status, since it was screened and shown among various locations before being released on DVD/Blu-ray here. It should also be noted that this did get a limited theatre run in Japan.