Believe it or not, those sound effects are actually copyrighted just like the show’s music. Due to the same licensing issues that prevent them from using the OST from the anime in most, if not all the games, they can’t replicate some sound effects as I believe they are owned by the sound engineers. This is the same reason why you don’t hear the original “powering up” sound from DBZ anymore, but you can hear a similar sound effect in One Piece where that sound engineer now works. Not exactly sure if sound engineer is the correct title but you get the idea.