Fan content legal question

Hi,
I would like to know if it is legally allowed, to use sayings or inside jokes from Fortnite (that developed by the community by playing the game) and use them commercially, i.e. for printing?

No images, no logos, just text with inside jokes.

So basically it is a reference to Fortnite. Is that allowed?

Regards

The floss like a boss is one example that is very popular.
Is it legally allowed to make a design that says “Floss like a boss” and sell it?

If it does not contain Epic IP, such as copyrighted or trademarked material including the Fortnite name/mark itself, this is permitted.

If it does contain Epic IP, it is subject to our fan content policy (Epic Games Fan Content Policy | Rules For Content Creation - Epic Games), which generally prohibits commercial use.