So I discovered this in the news: https://blogs.microsoft.com/on-the-issues/2020/01/09/artemis-online-grooming-detection/ (Or more easily readable: https://www.engadget.com/2020/01/09/microsoft-project-artemis-online-child-abuse/?guccounter=1 )
I think this is something that is a good idea to add to Discord as there are a lot of stories going around that Discord is home to child predators. This could be a great way to work against that. Either for all the chats or for just DMs, which sounds more logical as most child predators will do this in a private setting. Or maybe have it be part of the privacy settings for "Keep me safe" and/or "My friends are nice".
There are multiple ways of implementing this and I think Discord (or maybe even the community) can find a good way of implementing this.