Create an Operator Preset that can be reused and is compatible with Unreal Engine 4:

1. In Blender's main menu bar click File -> Export -> FBX (.fbx)
2. In the Blender File View window
   1. change the settings Include ->
      1. Enable Selected Objects
      2. Only enable Mesh in Object Types to export.
         
      3. TODO Armature
   2. Transfrom ->
      1. Forward -> X Forward
      2. Up -> Z Up
   3. Geometry -> Smoothing -> Face
3. Create the Operator Preset with the + button.

Hint: You can also export a pose by selecting / activating the pose and additionally enabling Geometry -> Apply Modifiers in the Operator settings of the export window.

Export the low resolution, retopo model(s) to Quixel Mixer or Substance Painter for 3D painting:

1. Again: Make sure all your models with the redone topology of the atlas have their own, unique material per UV map.
2. Set smooth shading for organic and hard surface models with normal map.
3. Select the neutral pose aka T-pose of your model(s) you want to use to paint it, that fits exactly the sculpted model.
4. Make sure that the models have the postfix _low.
5. Switch to Object Mode the 3D View and select all objects of the atlas you want to export in the Outliner Editor. Then click 3D View menu bar -> Object -> Apply -> All Transforms.
6. Export the statue as LowResStatue.fbx.

Repeat these steps to export ( as HighResStatue.fbx ) the high resolution, original sculpt model(s) with unique materials with the postfix _high to Substance Painter to bake for example the normal image texture.

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