Hello,
We won't develop something like this, because you just aren't supposed to change playroom sounds.
In v2, you could do it, most of the time it was working, but sometimes we received complains about a specific thing no longer working, that there is no longer sound, or because one single sound is used for different unrelated things. Some people changed their sounds, and, as a result of that, some little things were no longer working as well as before.
We don't want to make suppore any longer with those people, it's just a waste of time.
In v3, the fact that sounds are emcrypted should clearly raise an alarm in your head: changing them is forbidden, and if you still do it you are left on your own.
In clear, do it at your own risks. And in any case, we won't develop any tool that would help you doing that.
That being said, if you have ideas of good sounds that could replace existing ones, or want to suggest your own creations, feel free to post them publicly. Maybe we could add them in a future version of the client.