Server-Side Rewind makes a shot fair for a player on a bad connection: the server rewinds the target’s hitboxes to where they were when the client pulled the trigger, and judges the shot there.
Most write-ups stop at that. This one covers the half that bites later - rewind stops being fair at some point, and a shooter far enough behind starts killing people who were already behind cover. This is how to find that line, turn rewind off past it, and tell the player why.
Includes the ping-check loop, the per-weapon toggle, the values I ship with, and the frame-time trap that makes ping read high on a perfect LAN.
https://dev.epicgames.com/community/learning/tutorials/19mJj/server-side-rewind-in-unreal-engine-5-and-when-you-should-switch-it-off