It took me a minute to even find a solid answer because 'Meme Queen Novel Adventure' sounds like one of those fan-nicknamed things, but after some digging, I think you're asking about 'The Adventures of the Meme Queen' by Arathorn. The core plot follows this university student, Linnea, who gets isekai'd into a fantasy world, but her only 'power' is an encyclopedic knowledge of 21st-century internet memes.
She quickly realizes the world runs on a kind of narrative logic, and by deploying the right meme at the right time—like posting a 'Distracted Boyfriend' image magically to cause literal confusion in a royal court debate, or using 'This is Fine' dog energy to ironically survive a dragon attack—she starts manipulating events. It's less about combat and more about social engineering through absurdist humor.
The central conflict arises when the kingdom's serious, by-the-book crown prince has to ally with her to stop a demonic invasion. He's completely baffled by her methods, which seem frivolous but are unnervingly effective. Their dynamic drives a lot of the story, as she teaches him that sometimes chaos and nonsense are the perfect weapons against an overly rigid evil. Underneath the jokes, there's a theme about how modern internet culture is a new form of storytelling and weaponized irony.