Here is the harsh reality: The LFS Mod will not work on a standard, updated installation of Diablo 2 Resurrected if you simply drag and drop files. Why?
Without the Offline Fix, you will encounter one of these errors: diablo 2 resurrected lfs mod offline fix for v exclusive
Just having the files installed isn't enough; you must tell the game to load them via command line arguments. Here is the harsh reality: The LFS Mod
How to do it on Battle.net Launcher:
Mods are officially supported by Blizzard for Offline and Open Battle.net play only. Using mods on Closed Battle.net will result in your account being banned. The following guide is strictly for Offline Mode. Without the Offline Fix, you will encounter one