Angie Harmon (Rizzoli and Isles) wanted to do it too at one point and, apologies to Plaza fans, I think she'd be a hell of a better pick at least for when she's transformed. She's 5'10" - Jennifer Walters [NOT *Jessica* Cinema Blend, Google exists for a reason] is supposed to be much smaller, so they could film Harmon with forced perspective shots? It'll probably depend on which side of this character gets more screen time: since Jennifer traditionally prefers to stay as She-Hulk as often as possible, doing the thing where the effects-heavy work is on the "normal" person so that the hero is just the actor after physical training sounds more cost-effective (think Chris Evans going from puny to jacked in Captain America). Plus, that would technically be SW, right?
https://www.youtube.com/watch?v=DrDBJPe_ZWA