Simply having the files is not enough to play the game, as Fortnite requires a connection to Epic's servers. To run an archived build, users typically need:
Replay files cannot be viewed as standard MP4 videos. You need the Fortnite client to play them. However, for a truly portable review experience, use or Fortnite Replay Manager (FRM) . These are lightweight (under 10MB) applications you can store directly on your archive drive. They allow you to: fortnite builds archive portable