Actually… Did RyuuRogue sub mov.1? Their subs are usually good.
Yes, they did: https://ryuu-rogue.livejournal.com/37379.html
Also I found links explaining the Kazenban: http://dogasu.bulbagarden.net/movies/pm_mewtwo/mewtwo_strikes_back_kanzenban.html
and a comparison between the Japanese version and the English (4Kids) versions: http://dogasu.bulbagarden.net/comparisons/movies/mov01.html