YouTuber Speclizer found several pieces of unused multiplayer armor for Ellie while scouring through The Last of Us Part II's hidden game files. It's possible such content represents remnants of the multiplayer suite originally meant to launch alongside TLoU Part 2. Sony and Naughty Dog teased the return of TLoU's Factions after announcing the sequel during PSX 2016. And it was widely known that work had indeed begun on the online component. However, in September 2019, the development team confirmed plans to set aside Factions in favor of focusing on wrapping up the single-player experience.
In the two-plus years since then, The Last of Us Part 2's Factions has yet to officially see the light of day, barring the occasional rumor. One bit of speculation, based on job listings, posits that Factions will launch as a standalone experience, wholly separate from the main game. While Naughty Dog has yet to corroborate as much, the studio's minor multiplayer tease for The Last of Us Day 2021 referred to Factions as an ambitious project that needs time to fully gestate before entering the spotlight. When that time will come to an end is anyone's guess.
YouTuber Speclizer (via GamesRadar) recently unearthed multiplayer armor for Ellie in The Last of Us Part 2's game files, thanks to help from modder Angel-gbc on YouTube (known as Angel_Gbc10 on Twitter). Three different sets of armor featured in the hidden files, each of which Speclizer managed to capture footage of in-game. The Level 1 armor adorns Ellie in Police riot gear. Meanwhile, the Level 3 attire looks like gear once worn by FEDRA. Finally, Level 3's armor set bears a brown and green camouflage design. The YouTuber doesn't know the specifics of the multiplayer armor models' origins but speculates the unused files were likely "placeholder models" that stemmed from Naughty Dog's sidelined development of TLoU Part 2's Factions mode.
The multiplayer gear for Ellie could also offer a tease of what Naughty Dog has in store for the eventual release of Factions. However, given that TLoU 2's online counterpart remains shrouded in mystery, all anyone can do is speculate. As mentioned previously, job listings have provided a few hints here and there over the past year or so. A recent job posting made mention of in-game revenue and lifetime value, suggesting Factions could constitute a free-to-play experience with microtransactions.
Sony and Naughty Dog shipped The Last of Us Part 2 in June 2020 to widespread critical acclaim. The Last of Us sequel has since taken The Witcher 3: Wild Hunt's spot as the most-awarded game in history, with at least 300 awards to its name as of April 2021. Whether or not the development team plan to explore a third entry isn't yet known, though series Co-Creator Neil Druckmann did tease that he and TLoU Part 2 Narrative Lead Halley Gross previously drafted a story outline that hadn't entered development.
The Last of Us Part II is playable on PS4 and PS5.
EDIT 02/27/2022: Article updated to include credit for modder Angel-gbc.
Source: Speclizer/YouTube, Angel-gbc/YouTube, Angel_Gbc10/Twitter (via GamesRadar)