Yes this is mostly an engine limitation I chose because of my knowledge of ue5 (starting a new project instead of migrating later). I thought I wrote it in the documentation but I also wrote it a long time ago so sorry if you couldn’t find anything about it.
But since the migration features seem more plentiful in ue5 than in ue4 it seems to worked out okay. You should be able to migrate single files with right click and asset actions or maybe with this tutorial https://dev.epicgames.com/community/learning/tutorials/zBe0/unreal-engine-how-to-move-assets-to-another-project-
I wish you luck and feel free to tell me if you chose to migrate the files from a new project or if it was too much of a hassle.