Well, the audio only plays automatically on correct reading answers on vocab. You can set this in the app settings, so you don’t need a script for that.
There is a script that delays moving on to the next item on a wrong answer, I think: [Userscript] Wanikani Mistake Delay (new, version 2.x)
I don’t know about the website, but I know the Flaming Durtles app does it automatically.
This may be of use to you as well. I use it anyway.