A new The Last Of Us mod that’s currently being worked on appears to be changing pretty much the entire game by changing one half of the game’s core duo. According to the mod description, the minor character Tess instead takes the role of Jole in the game as Ellie’s guardian.
In the original Last of Us game, Tess was a minor character and Joel’s partner who originally was helping him get Ellie to the Fireflies. However, as the trio try to leave the city, Tess reveals that she was bitten while sneaking past a group of Clickers and thus doesn’t have long to live. She then sacrifices herself to buy Joel and Ellie time to escape from the military.
Considering that, Tess doesn’t really have many lines beyond the first segment of the game. While she does apparently work with the game’s cutscenes, Tess doesn’t have very many vocal lines, though she can get various grunts and and hair physics to match up.
This isn’t the first time that a The Last Of Us mod has been created by the YouTuber in question, Freako. Freako has previously made other NPCs replace Joel in the game, including Marlene, the leader of the Fireflies, Joel’s brother Tommy, and Tess.
While Marlene didn’t necessarily work out in the main game, Tommy and Tess worked fairly well with the replacements. However, the mod is still under construction; Freako likely still has a lot of work ahead of him if he wants to fully implement Tess into the game.
Whether the Last Of Us mod will even be available for download is another story; Naughty Dog doesn’t allow mods to its games on consoles like Bethesda, so there’s likely no way (aside from altering the console itself) that you could put a mod like this onto the console.