You can just use a USB. Cloning your directories and copying them over is how backups work. Copying the files over as they belong accomplishes installing the game.
Cloning on Linux
Use the rsync command in Bash to clone directories.
Open Terminal
Command:
rsync -avh /path/to/source/ /path/to/destination/
Replace /path/to/source/ with the path of your game directory.
Replace /path/to/destination/ with the path to where you want to clone the directory.
Replace C:\path\to\source\ with the path of your game directory.
Replace C:\path\to\destination\ with the path for where you want to put the files. Probably the USB
You can just use a USB. Cloning your directories and copying them over is how backups work. Copying the files over as they belong accomplishes installing the game.
Cloning on Linux
Use the rsync command in Bash to clone directories.
rsync -avh /path/to/source/ /path/to/destination/
Replace /path/to/source/ with the path of your game directory. Replace /path/to/destination/ with the path to where you want to clone the directory.
On Windows
You can use PowerShell
Copy-Item -Path "C:\path\to\source*" -Destination "C:\path\to\destination" -Recurse
Replace C:\path\to\source\ with the path of your game directory. Replace C:\path\to\destination\ with the path for where you want to put the files. Probably the USB