Video Editor is a feature introduced in the 3.0.0 update of Super Smash Bros. Ultimate that allow players to manipulate any replays they've recorded in-game. Multiple replays can be spliced together with a selection of transitions, and can also be garnished with a single set of subtitles and any track from the game's extensive soundtrack.
There are five different options when a video is chosen for edit: delete, copy, split here, transition, and audio. Once a video is finalized, it can be exported and uploaded to either Shared Content or Smash World, where they are subject to the same moderation system as other uploaded content.