First of all, Hero represents Zhang Yimou's image style to the extreme. To put it bluntly, it is the use of colors: all kinds of colors look as complicated as the plot, but they are not dazzling. Different colors are collocated in the same scene and picture, which make each other interesting. Every scene and story uses color blocks, which do not conflict with each other.
Then there is the story structure: the whole film is three ways to express a story. In the question and answer of the characters, the story slowly advanced and the result was quite shocking.
I hope it helps you _