I doubt it is going to be exactly the same. I suspect it is going to be like a stretchy energy based exoskeleton. And there are probably a coupe reasons for this.
1. Kamala's use of her powers are very goofy looking when translated into live action. Even the video game didn't exactly make her powers look appealing. And it is important to remember, while her powers are similar to Reed's, the usage is very different. Reed doesn't do the whole embiggen thing, and a lot of his stretching is less the weird proportion stuff that goes with Kamala. (And yes Darth, I acknowledge the reason for this from Wilson)
2. Visual and thematic synergy with Carol and Monica. They are going to want their Marvel family of characters to be visual complementary. They are going to be ****ing power rangers, with similar, but visually synergistic powers.
3. And likely reason, and the one less talked about, the budget. Doing an big energy fist is going to be a lot cheaper and quicker than a giant hand.