How should I dress to disguise the fact that I'm underweight?

I’m struggling with my style because I’m underweight—not just 'skinny,' but thin to the point where I lack muscle definition. I feel like oversized clothes just swallow me up, making me look even smaller, while crop tops or tight fits make me look too fragile. Currently, I rely on wide-leg pants and thick long sleeves to disguise my frame without looking too bulky, but I feel like it lacks elegance and personality. Does anyone have any styling tips or fashion icons I should follow to look more well-proportioned and chic?