When I export as fbx, import + edit in Blender and export to UE4, my skeletal mesh has changed

Hey, I don’t usually ask for solutions and try to find them myself, but I’m stuck for several days. My problem is when I export (via fbx export) a mesh that has the same skeleton as ALS V4. I import as fbx & edit it in the blender and delete everything on my char mesh except the pants, because I want to give my guy clothes. When I’m done, I export it again as fbx and import it from UE4. But the problem is, when I select the skeleton of my char it says “Failed to merge Bones”. After I click on “No all” and try to fit the pants to my character and his animations, the pants don’t fit and are bent. I think, that when I export it to Blender my IK Bones are gone or are renamed. Please, if you are reading this and have only one suggestion Post it anyway, any help is welcome here.

Here is a Google Drive link, which will lead you to pictures to understand it better.
https://drive.google.com/drive/folders/1uRLCDAtsCy-nbRVBoSRY6KzQGOV8JiaN?usp=sharing

Sorry if you don’t understand the text so well, my English isn’t so good :smiley:

I have found a solution. My bones had the original names of the mesh instead, the names from the UE4 mesh. I just had to rename each bone. :smiley: