Hi,
I successfully tested the “migration” process from UE4.16 to UE4.7 (!):
- from your source project (UE4.16), select the asset you want to migrate
- right clink on it, then select “Asset Actions” > “Migrate…”
- a recap of what assets will be migrated is show, click “Ok”
- navigate to your target project (UE4.12) and select the “Content” directory, then press “Select Folder”
- the message “Content migration completed successfully!” appears
- go to your UE4.12 project and you’ll find all the migrated assets (in the same directory names as in the source project)
I also tested the migration of the “skeleton” asset only (again from UE4.16 to UE4.7), and it works. Of course if you try to open the skeleton in the destination project, you’ll see nothing - as the skeleton has no mesh, it’s only a hierarchy of bone names. If you migrate the character skeletal mesh instead, you’ll end with both the skeleton and the mesh available in the target project.