If you decide to go this route, here is your quick setup guide:
This is the gray area. While Fitgirl does not host copyrighted files directly (she uses magnet links and torrents), downloading the repack is technically copyright infringement because you need the core game files (MPQs) which are owned by Blizzard Entertainment. Diablo 2 LOD 1.13c Portable Fitgirl Repack
However, there is a legal nuance:
Our advice: If you love the game, buy a legitimate key for Resurrected (which includes the classic D2 client) and then use the Fitgirl repack for modding convenience. This clears your conscience while giving you the portable file structure. If you decide to go this route, here
In the modern era, convenience is king. Finding original Diablo II installation discs is difficult, and even digital legacy installers from the old Blizzard store can be finicky. Our advice: If you love the game, buy
This is where the Portable Fitgirl Repack comes in.