Filecrypt

One file is offline. The other downloads directly from the server.

A plugin could be created by getting the response from the server.
Using an if statement, if the server returns an error, then mark the file offline. Else, mark online

Pseudocode / rough code

Code:
var downloadURL = dl.kingdom-leaks.com/files/{filename}

if (downloadURL.getServerResponse()=4xx || downloadURL.getServerResponse()==5xx)
{
folder.markOffline();
}
else
{
folder.markOnline();
}