While Avowed has been compared to Skyrim, its gameplay is more akin to Obsidian's The Outer Worlds, a single-player experience. This begs the question: does Avowed offer multiplayer capabilities? The short answer is no.

Avowed lacks both cooperative and player-versus-player (PvP) modes. You'll journey through the fantasy world with companions, but these will be non-player characters (NPCs), mirroring the structure of The Outer Worlds. Enemy encounters are also entirely AI-controlled; there are no player invasions or similar features. While initially planned, multiplayer functionality was ultimately cut during development.
Obsidian Entertainment's decision to remove multiplayer stemmed from a prioritization of other aspects of the game. While initially used as a marketing tool, the developer determined that focusing solely on the single-player experience was the best path forward.
Currently, no Avowed co-op mods are publicly known, although the possibility remains. Creating such a mod is a significant undertaking, and Obsidian has confirmed they have no plans to add multiplayer post-launch.
Therefore, Avowed is a strictly solo adventure.