Normal Maps seem to be baked with Low Poly Details UPDATE:


Tried my best to retopo the thing a bit more clean and twist the Y for DirectX.
Maybe I have to practice topology, because the result seems still underwhelming, it doesn't look like the sculpt by any means. :/



OLD:

I am trying to get a normal map from a high poly torso and get it on the low poly model in Unreal. I checked the Bake Settings, tried different solutions for the base mesh, the end result always looks like this:



It seems to be a combination between the low and the high poly model. 

But the idea is to get only the surface of the high poly model, right? Or am I completely wrong and I simply can't hide the low poly surface?
On top of the above, I've tried numerous things. Subdivision helps, but it only looks good if I set it to 6+ and then every performance + for games is gone and the whole normal map thing is redundant.

The red circles show a few edges that are slightly "off", but they don't seem to be responsible for the overall bad quality of the map. 

The lines that I marked in the purple normal map image are exactly those from the low poly object. What are they doing there?

PS: Maybe the problem is that the low poly mesh is wrapped around the high poly? I thought it is good this way but maybe it has to be the other way around?
The main problem is that you are baking a normal map suited for OpenGl. Unreal uses DirectX normal maps. You can easily solve this by inverting the green channel. It can be done during bake in blender, in photoshop or in Unreal in the material.



The dark scene in Cycles needs some lights to be useful. But if you need to have it shown correctly with the DirectX normal maps you need to invert the green channel in the material.

The next problem you have, is the artefact which is caused by a very thin triangle. (Even it you don't see triangles, all faces will be split into triangles during rendering and baking.) When the normal bends over the face and there aren't enough pixels the baker will not be able to create that bend without aliasing. The fastest way of fixing this is to give that face more room on the UV map. That would increase the resolution for that area only. But the better way would be to avoid thin triangles.