The first version of the normal map conversion tool Handplane has been released
"handplane is a new tool designed with the goal the of solving tangent space mismatch issues for everyone. handplane works by combining an object space normal map with a lowpoly model to create and engine specific tangent space map. This means that artists can continue using their existing baking software to create tangent space normal maps synced to the following engines:
You should also checkout the other videos that are on the site, they go over a lot of general knowledge about normal maps and shading which can be a pain in anyone's side.
"The more you know, the better your workflow".
We are talking about it HERE