Why don't you be a real Gipetto and carve your own?
You did your homework on what you thought would work. Sometimes that's how it goes. As a guy with drawers and totes of parts and figures, I always feel like I can make something work with some experimentation.
I didn't realize the wrist pegs between SS and SE were different. And their arms won't hold a 90 degree pose? Wow - I haven't seen that happen.
I’ve done that before. I’ve Frankensteined my fair share of bodies to achieve what I’m looking for on quite a few occasions. I have multiple spare parts from many different bodies lying around and mix-marching them is nothing new to me. Over the years, I’ve experimented with nearly every available body in this hobby across multiple brands and when one breaks, I salvage all usable parts down to screws, internal posts and springs (usually at the waist joint) and even the elbow and knee joints.
Nothing I had worked in the way I wanted it to for this particular application. This is why I say in my original post that using the Phicen/TBLeague body was a last effort in trying something out before deciding to sell it.
The only fully body that I have that I didn’t use was the all black HT Concept Cap body but I’m saving that as that’s a vary hard body to come by. I have the parts to sort of make one, but it would require making a particular shoulder hinge joint. I’ve done it in the past but I don’t enjoy making them.
But yes, neither stock figure gets to a 90degree bend and stays there willingly. And I’ve bought spare Snake eyes bodies that I was going to use to port the original sideshow figures onto as I thought they’d be good ones to use to update those figures with, but didn’t turn out to be good ideas, at least for me. We all have different wants/ideas though when it comes to these type of things, so what doesn’t work for me may work for you as evident by your own experience with the Storm Shadow body.
I was planning on using the world box AT012 body. The one used for wolverine.
Off the top of my head, I can tell you that the feet aren’t a 1:1 swap. The ball joints that 3Z uses are smaller than what is more standard like what Worldbox, HT and other brands use. So for that alone, you’ll either have to shave down the ankle ball joints on the Worldbox to fit inside the socket in the 3Z feet or switch out the socket in the feet like I did.
I’d have to verify when I get home if either wrist pegs can be used.
The arms are relatively the same size, so you shouldn’t have any problem there ideally.
You shouldn’t have a problem with the pants fitting either as both the stock body and the Worldbox have a pretty narrow waist.
If you do decide to proceed, be prepared for some seams to potentially pop while trying to get the shirt on that body. With how wide the chest/shoulders are and it being a hard plastic, getting the shirt on will be a little difficult since you won’t have any real give in that area. That body also doesn’t have a butterfly joint at the shoulder if I remember correctly, so you don’t have as much flexibility when shimmying the shirt on. However, if you’re good with a needle and thread, I’d almost suggest undoing the seams at the sides of the shirt ( or at least one side) to make it easier to get it on the body. I didn’t think of this when putting the shirt on the M33, but it definitely would’ve helped.
Hope this helps.
I wish I knew how to photograph these things well, but even with modern phone tech, they still never come out how I see them in hand. And while I can see the more mass on the figure as well as the overall in hand quality feel, it may not look as impressive or different from pics, especially my pics 
But, I do like the difference more than any other body I've tried which is nearly every muscular male body on the market of similar size and it's enough to actually make me want to finally display him rather than keeping him in the box where he's been this whole time.
