Are you looking to to another computer or use them with a specific mod?
He copied the file to the desktop. Then, he closed the game, reopened it, and created a new, dummy character named “TEST.” He saved TEST, quit the game, went back to the folder, and replaced the new Single_0.sv with the old one. diablo 1 save file location
These were stored on Blizzard's servers, though local registry entries tracked character names. Are you looking to to another computer or