I cannot get over the quality of this 2D style shader. It really is breath taking. As an artist- I would love some insight on how they went about it. If anyone has any ideas, please share (and yes I realize there is probably quite a bit of custom work here, but would still love to see the breakdowns). When I look at work like this, it really gets me excited about Unreal4 and the breadth of the games that can be done with it.
The Guilty Gear shader looks amazing, I even like the little touch of repeating frames on the animation and not tweeing between them just like the old school 2d SNK games.
I’d love it if someone comes up with a tutorial on how to achieve this look.
In the mean time there’s this tutorial on how to get some stylized renders but not exactly what Guilty Gear is doing.
wow thats amazing, yeh there must be someone out here good enough to give this a go, alot of people want something like this! 
It’s too much work to do something like that for free, Maybe on the marketplace I will give it a go. For now can’t find the time.
I may not be the guy that know how they did it but if your interested on how the cel shadered was made you can look into this thread. I’m trying to come up with something Guily gear Xrd for a while now.
It must take a lot of talent to do this 
since it seems like this is the best of its kind at the moment…
Most of this is not going to be accomplished through the shader. The method in which you paint your textures, sculpt detail in models, etc. is going to be the main locomotive for accomplishing this. An art style like guilty gear is “Geared” around a pipeline to fit the artist style. A shader alone is far from good enough. If anything, the shader they use simply marries tones/colors, and deals with shadowing/stencil vfx. Everything else is done through painting and sculpting skill.
(Unless a magic button has been created that I am unaware of)
In which case - Please share 
There is no magic button or node. But this really is a highly custom shader though. From what I can glean, they make the direct lighting lambertian tight with zero falloff and have really ace outlines, neither of which is textures or modeling. But you are correct in saying that the shader’s effectiveness is somewhat dependent on artist created inputs eg textures and meshes.
…
there is a thread on polycount
http://www.polycount.com/forum/showthread.php?t=121144
make sure you go to the last a few pages which contain some useful info on how they did it and of course dont expect some magic shaders of doing it.
There’s a GDC presentation on it:
Basically the shader is noddy as hell and only does simple 2-3 tone cel-shading with vertex-colour-attribute threshold control so the artists can control the shading on a per vertex basis. Colour seems to be defined through two textures multiplied and careful uv manipulation is used to define clean, resolution-independent internal lines. The outline seems to be done the old fashioned way, i.e. inverted-normal-expanded darker mesh generated and drawn before the main one without z-writing.
I’d sure like to know if this is even possible to do in UE4, especially given they use local light sources, I.e. no global light source but local light vectors per model.