Well aren't both versions on the same ROM, and the game just switches between SoR and BK based on what region the console tells the cartridge it's from? I saw a YouTube video where a guy modded his Genesis to have a switch that toggled it from Japanese to American. He used it during the intro for some Streets of Rage game (the first one I think), and the text crawl changed languages part way through. Like the first few lines were in Japanese, then the next couple lines were English, and then it went back to Japanese for the last couple lines, with both languages staying onscreen.
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SuperNiceDog didn't have to reconcile his name...
But Dauntless Hunter is now MrGreenonion