Being an experience side character had taught Zhao Youyue to be good at reading people. This resembled the saying that goes, "Spectators see the chess game better than Players."
As she was used to observing the world as an outsider, she would see through things in a matter of seconds. Nobody could possibly dupe her. However, she was no better than her would-be manipulators; she would not unmask the perpetrator on the spot, as she would be curious to see their game to the end.
Although she was no longer a side character, her ability to "see through" was still there.
In the beginning, she had already known that Shen Menglian had her own schemes, while Bai Yunshan was a cute figure of pedantry who stood up against every manner of misdeed. She never told lies, she spoke it as it is.