It probably takes a historical drama fan with a keen eye to recognize that the actress is completely dressed as man (despite looking very womanly anyway). And no, this is not one of those instances where the woman pretends to be a man because the role of Wang Yi Zhi is literally a male supporting character in the novel and a fan favorite too.
I honestly find the whole idea unnecessary (because surely there are actors who could rise up to the challenge), but it’s not unheard of. It worked in 1992 with New Legend of Madame White Snake and it could work here. In all honestly though, I’m beginning to feel like I’m just here for the laughs.