Exporting from Blender with correct bone orientation

Hello everyone,

I am having a trouble explorting a Mixamo rig from Blender to Unity. My goal would be to have an humanoid rig, where each bone has the same local coordinate system than the global one, like this .fbx that I already have:



Then, I want to import the same .fbx in Blender to make some changes in the 3D model (in the "Import Armature" options, I check Force Connect Children, and Automatic Bone Orientation (Primary axis Y, Secondary axis X). The problem, is that the local coordinate system change.

For the hips, for example, in Edit Mode, the local system is displayed as it was shown correctly in Unity (both SW share different coordinate systems, therefore in Blender they are rotated 90° if I know correcty). BUT in Pose Mode, the system follows the bone orientation which differs from the original local one.

Edit Mode:



Pose Mode:



When I export the .fbx of the very same model with the following options, and then re-import it to Unity, the bone orientations changed, without doing any (intentionally) change in the middle of the process.

Export Options:





Therefore, I guess there is a problem maybe with the import/export settings? How could I import the original model and export it to have the same coordinate systems per bone?

Thank you.