Catherine is described as a "vision of radiance" in the first episode and is portrayed accordingly. The historical Catherine was considered a beauty.
While it's Velementov who describes her as such and also Velementov who lusts after her, the trope Informed Attractiveness is about the story telling us the character is good-looking regardless of what they actually look like.
This was removed from Informed Attractiveness and moved to Lust Object:
While it's Velementov who describes her as such and also Velementov who lusts after her, the trope Informed Attractiveness is about the story telling us the character is good-looking regardless of what they actually look like.