At the moment my remote repository is on my development PC (Windows) on a separate drive. I want to move it to my Synology NAS box.

When I Google it, I can only find very complicated methods. Is there anything wrong if I
physically copy the directory structure over (I know it's a different OS, but surely the files should be the same). I have "core.autocrlf" set to false.

Before someone tells me, it should be outside my house, I have a NAS box at my batch, and I intend to replicate information there.