Crossing Doupo to Dominate the World

Accidentally transmigrated to the world of Doupo Cangqiong, a world where martial arts are revered. Accidentally saw the secrets of Xiao Xun'er, who has a super powerful background, and was hated by her. Xiao Yan, the protagonist, seems to have an invincibility aura too, how can one even survive! Fortunately, there's the cosmic trading system, which can turn all useless things into useful ones. This is doable, let's see how I turn Doupo Cangqiong upside down!