If I'm to believe the AI overview (as you said, Google is useless), Enter the Dragon was the first film to feature his actual voice and it's an English film. I don't think I have but one audio track for that . Earlier stuff is dubbed. Search result explanations is that many Hong Kong movies at the time were shot silent then dubbed afterwards. That would make sense, since the "Chinese" audio track I have for Way of the Dragon seems to fit the lip movements rather precisely but it isn't his voice. I'd have to check the other films to confirm they're the same.
Your list, sure you're aware, matches the Bruce Lee Criterion Collection set. I'd be adding "criterion" to the searches, if you're not already, and hoping someone has full-set rip with multi audio and subs. I got remarkably lucky and my local library actually had the Criterion set (along with some "Universal Horror" Karloff and Lugosi films) so I was able to check them out and rip them myself. Depending on where you are and your local infrastructure, might be a good shout to check your local library too.