Hello, I have a problem with migrating my project.
When I do it, the migrating assets do not show in the new projects. The files are there, I can go to the content folder, all the files are physically there, so they migrated, but when I open the project I only can see empty folders.
Migrating to an earlier engine version doesn’t work. Is that it?
In the main unreal window in content browser, right click on content folder and select fix up redirectors.
Just taking a shot… it may or may not work.
You can also try using the reference viewer on some assets to see if the references exist at all.
Sadly it did not fix it for me. But thanks. 
Migrating to the newer version or the same version.
When I upgrade the project from 4.27.1 to 5 it also happened.
Textures and materials are there but the blueprints are not. It is like the files that I created or edited are invisible for the engine.
Ok, weird.