Legal question: What content can I use in my game?

Even if I create a new project without the starter content there are still a few animations and sounds. This may be an irrational fear but If I create a game and actually publish it and make a dollar could EPIC come back and sue me if they found some obscure sound file I didn’t know about. I know this might be a little ridiculous but I don’t want to work on a game and not be able to publish it when I’m done because I didn’t cleanse the folders the right way when I started. I’m not interested in the odds that they would sue me for a dollar I’m interested in how to properly and safely “start from scratch”.

Here you can read which content you are allowed to use: Can we use sample content in our own games? - UE4 AnswerHub