Yes it’s better rescaling.
The problem is that only 7 volumes where created for bones, and my character have 15 bones. So how can we do to add missing volumes ?
I looked at the steps from FBX import :
https://wiki.unrealengine/Creating_a_Skeletal_Mesh_in_Blender#Creating_a_New_Scene
So the character in the scene could it be static or animated is ok now , with same orientation and scaling, this works when i follow these three steps import : 1) import static 2) import riggged character 3) animations import
There is still the frames number issue and physic volumes number issue.