Maybe the reason the girl(Tifa if I am right) that she can carry those in front of her is because she has the right amount of str also it might be from her own luck.
The translators are right she's a high-level tank. It's just that it's not the kind of tank you're thinking. @AbuHajaar That's right, you get it. I'd dare say it's not just a tank, with that size it's an entire reservoir