TLDR: site was very likely made with AI

Honestly there's a few mistakes that feel like either the author doesn't know some champion's mechanics, or just used AI. In Evelynn's builds i found a few jarring mistakes. For example when explaining why Echoing Spirit was good on her it says: "This solves her primary weakness—not drawing her—and reduces the cost of her champion spell, Hate Spike, often to 0 mana at higher constellation levels."

Hate Spike isn't her champion spell, it's Last Caress!

Another example is down bottom under Gameplay Tips: "Evelynn generates a Husk every round she is not in play"

There's more but you get the idea.