Do we count television cannon? Because logically, if he transformed into a Pokemon, so did his vocal chords, and he shouldn't be able to talk. But Meowth can talk because apparently the guy who blasts off every single time is the only Pokemon smart enough to teach himself to talk, or the only one who bothers? The TV show makes no sense, but in game cannon, Bill is just wearing a fursuit. I don't remember if Meowth talked in Yellow.
