Batman: Arkham series
Harry Potter franchise
Mortal Kombat franchise
Details and Conditions
WB Games is also known as Warner Bros. Interactive Entertainment.
There is no official statement on the matter from WB Games that I was able to find online. However, several people seemingly have attempted to contact them on the matter throughout the years. From what I can see, WB does not allow monetizing videos but is fine with videos being made available for free to view through streaming (which means no Twitch Subscriber-only streams).
There's also inconsistent responses from WB from quoted emails that people have sent in regards to conditions for videos on YouTube. For example, one user was told a video cannot be past 5 minutes of length and cannot use music. This could be on a game-by-game basis and may also depend on the developer for each game, so you may need to send emails to their support for each individual basis.
It makes sense that WB would not approve monetization. Much like other publishers in this list that do not have a statement or just flat-out deny monetizing videos, WB works with a lot of licensed properties. While their parent company might own rights to movie properties like Harry Potter, or subsidiary properties such as DC Comics characters, like Batman, that doesn't necessarily mean that assets and characters used in those games from those properties would be approved for YouTube monetization even if WB Games did provide approval. This is likely why they responded to that one user to not use the music featured in the game in question.
There are also games with several licensed IP. For example, I was asked about the LEGO games that WB publishes. So I'm going to go with the most complicated example I can think of. Let's say you're looking to monetize a video for one of the LEGO Marvel games. First, you would have to contact WB Games for permission since they do not have a statement online on their website. If by chance you somehow got approval from WB through email (which is extremely unlikely), you would also want to get approval from The Lego Group as well as Marvel Comics or its parent company, Disney. Getting approval from either of these companies would be even more unlikely than WB Games. Additionally, if there's any copyright music or anything taken from any respective movies or TV shows, it might trigger copyright claims on your video that would prevent you from monetizing your videos or could result in the video being blocked, deleted, or a strike on your channel. For more context, please read the page I made for important information like this.
If you're searching for approval on a WB game, you would probably have better luck with games under their own IP, such as Hitman, Mortal Kombat, or indie developed games like Bastion (which the developer, Supergiant Games, already approves).
What it Means
Videos and streams SHOULD be allowed
You CANNOT monetize on YouTube and Twitch with ads and subscriptions
You CANNOT sell or charge for access to your content (this would include Twitch "subscriber only" streams)
Any licensed IP or music not owned by the publisher are not covered by this policy