I did the same thing to Snow Way Out! I just made up some lines for what I thought they might say in the English version during the match scene in the igloo. I played as James and my sister played as Jessie and I re-arranged Meowth's lines. I have it recorded on VHS somewhere. I also want to dub all of the skipped episodes into English.
Also, I have the Japanese R2 DVDs of the first 3 movies which have selectable English or Japanese dubs. Those are pretty cool not only because of the audio, but also the fact that they are widescreen, unlike the US releases. The First Movie also has the complete Mewtwo's Origin that plays before the movie, and no glitch that has Bulbasaur? appear twice during the opening credits. Movie 2000 has an extra scene with Tracey describing why the explosion is about to happen. When viewed with English audio, this scene has no audio and a subtitle "NO SOUND IN ENGLISH VERSION". I'd like to re-dub that scene as well.
I don't think the rest of the movies have dual audio releases. I'm trying to find a widescreen copy of the English version of movie 4, since I hear there were additional scenes animated for the English release that are not on the Japanese DVD.
The only official English release that I know of contains English and Japanese audio is the GameCube game Pokemon Channel.