There is a smart hack that will autoplay with sound once get required microphone permission from users:
navigator.mediaDevices.getUserMedia({ audio: true }).then(function (stream) {
var x = document.getElementById("myAudio");
x.play();
// stop microphone stream acquired by getUserMedia
stream.getTracks().forEach(function (track) { track.stop(); });
});
It works because as long as you are capturing then you are allowed to play and then stop the microphone stream when your audio starts playing.
Otherwise, you have to instruct users to allow Sound Permission using site settings themselves which is technically weird.