It's possible. The quality of a manga doesn't solely depend on its class. A bronze class manga can have unique and engaging elements that make it just as enjoyable as a gold class one.
I don't know which comic I'm referring to. These two words were not very common, and there was no information about them in comics or novels. Please provide more information or context so that I can better answer your question.
Typically, these mangas incorporate elements of physical activity and competition in the PE class context. The characters' emotions and interactions play a crucial role. The plots can range from light-hearted to more intense and dramatic.
The Secret Class manga and manhwa could differ in character designs. Maybe the manhwa characters have a more modern and trendy look compared to the manga. Plus, the panel layout and visual storytelling techniques could be distinct as well.