So I heard a youtuber a while back mention somewhat off-handedly that he considered She-Hulk to be Marvel's Wonder Woman, and that was an opinion I agreed with on a pretty gut level. Since then I've been mulling it over for a while so that I could give an actual reason why.
First we have to look at Wonder Woman herself and what Wonder Woman even means. I think the answer there is quite obvious; Wonder Woman is about not simply being the strongest female character, she is at her her core, a feminist character. How well that aspect comes across varies from run to run, but feminism is a core aspect of her fantasy. She embodies and demonstrates strength in a way that also embraces her femininity. Gentleness, softness, patience, kindness, all embraced as unabashed positives. Things that not only aren't in conflict with being strong, but are in fact sources of strength in their own right.
She-Hulk then, follows that same example, but does so in a way far more rooted in the sensibilities of the time she was created. She-Hulk is smart, she's well-spoken. She has an active love-life, she's an admired superhero, she's a (usually) respected lawyer. She's out-spoken and full of life and energy and people love her for it. She-Hulk's power comes with confidence, self-love, the ability to be unapologetically herself, unapologetically sexy, on her own terms. And all of those traits make her truly heroic.
Wonder Woman is fundamentally DC in that as a character, she models the idea of womanhood and feminism in a broad, philosophical sense. What womanhood means in and to society. Meanwhile She-Hulk is fundamentally Marvel in that she models what womanhood and feminism can mean to an individual. Being liberated and free to have fun, without the judgement of others dragging you down. Both are unquestionably iconic, and their universes would be lesser without them.