*IS SUMMONED TO THE THREAD*
I've actually done some minor work with FF models (I attempted to print chess pieces using Ren's DC models, but it didn't pan out because of the work involved) and while it wouldn't be hard per se, there are some things to keep in mind
-The models are SUPER low poly. FF masks this as much as possible, but pretty much all muscle definition comes from the texture. While they wouldn't look awful at a small size (say, 1-2 inch range), anything bigger than that and you either need to do some serious sanding/resculpting, or upres the model manually before printing. What I did when I did my test print was I took the model, and then used C6's skin to create a poor man's bump map, and used a tool to actually bevel the mesh based on that bump map. I'm SURE there's a simpler way of doing things, but I'm not enough of an expert to know it.
-Exporting the model in specific poses without direct access to Max will be a pain no matter how you slice it. Using the in-game ff models makes things easier, since most have existing max files and you can get the poses from there, but if you don't have 3ds Max (and in this case you could theoretically use any version) you either have to A. rely on someone else who does have Max to do it for you (always a tricky thing) or B. you could manually pose the model in nifskope and export it... but I don't know how well that would work without experimenting with it.
-Anytime you're dealing with a model that was not made with 3d printing in mind, it becomes that much harder to keep details straight. Pretty much any printing material you use will have minimum thickness requirements, and you have to be SUPER careful that smaller sections (thumbs, noses, weapons, etc) are thick enough to survive printing. You also have to be wary of any bending joints... FF's joint system is not great, so there's a LOT of warping around shoulders, elbows, pelvis, and knees during some animations, causing them to become paper thin in places during some animations.
