Well, that didn't take long - that fancy in-game footage of what seemed like a Star Wars: The Mandalorian video game has been discredited by many industry professionals, making it clear that it is a fan project put together by an avid Unreal Engine 4 enthusiast.
The footage appeared on YouTube before making the rounds among the fandom, with many assuming right off the bat that is it leaked from an actual game - it was uploaded with a seemingly nonsensical title, and was recorded with a mobile device while running on a separate screen, giving the video a leaky "found footage" sense.
Showing off a main menu, traversal, shooting mechanics, a holographic weapon selection menu and the titular Mando moving through the interior of an Imperial starship, the apparently leaked footage looked very convincing. However, a lot of key errors also stuck out if you were paying attention that are now all the more obvious.
As the video started making the rounds online, professional game developers chimed in to state that this is definitely a fan project and not an actual licensed game's proof of concept. Sumo Digital's Jack Chapman pointed out that this is an Unreal Engine 4 mod with canned animations from Advanced Locomotion Systems. Funnily enough, a fake Google Stadia UI was modded in as well in what could only be an attempt to make the 'leak' look more legit.
Thats definitely a UE4 project using a package called ALS. I recognise that body animation anywhere! Looks like a cool fan made project tho.
— Jack Chapman (@ShakaInc) August 26, 2021
Canned animations, stock sound effects, overly shiny armor, a vastly undernourished Grogu, an unofficial guitar cover of the show's theme pulled from YouTube, loading screen text pasted from Wookiepedia, other videos on the channel with UE4 content and the fact that Disney's relentless troop of lawyers haven't nuked the video yet all reinforce that this is an impressive fan project.
The perspective and many assets seem to indicate that what we're looking at is an elaborate Battlefront 2 (the EA one) mod, or at least the project uses a lot of that game's underlying framework. If nothing else, the major news surrounding the video have reaffirmed how much people want a The Mandalorian game. Prolific modders often get hired out of turn - maybe that will happen now as well?