Can I import a picture of a person (no longer living) to create a meta human? I can’t get a scan.
You need Static 3D Face Mesh to generate MetaHuman
You can use some online tool like in this tutorial to reconstruct a 3d face model & export it → 3D Scan From Photos! Make a 3D Model With Free Software! - YouTube
Import that 3D model into UE5 and follow this simple straight forward tutorial → Using Mesh to MetaHuman in UE | Unreal Engine - YouTube