In Blender you can export uv layouts as png image, is it possible to use that image again for the mesh to get the same uv layout as in the image again?
- short: No.
- long: There is no information in the exported image about the original 3D vertex positions or the face loops. So this is impossible to do because the information is … well not anymore. This image is just to see where the UV’s are and are very handy to put in a layer while drawing the image texture… but if you do for example change or reset the original UV (while not adding a new UV map) this texture will go crazy over the mesh.