When it comes to outlines in UE4, how you set it up will depend on how predictable your camera positioning. Setting up a one-size-fits-all solution is hard, which means you'll probably use a mix of different techniques depending on the scene. If you're looking to slap a silhouette outline around individual objects that…
The shading seems to be the easiest part, it looks like they're using more shading steps than the Guilty Gear Xrd method, which uses only 2 steps (lit or unlit). You can see it on the orange vest there how it has 4 steps, and there's some smoothing on it too? On Guilty Gear Xrd they used the step shader instruction as a…