Since Elden Ring already has a complex and engaging story with a vast open world filled with different regions, each having its own backstory and secrets. The Shadow of the Erdtree is expected to build on this. It might explore the history of the Erdtree more deeply, perhaps uncovering ancient secrets or prophecies. There could be new characters introduced who have a connection to the Erdtree, whether they are protectors, seekers of power from it, or those who want to destroy it. The story will likely unfold through exploration, interactions with non - playable characters, and the discovery of hidden lore throughout the new areas added in this expansion.
Since the base Elden Ring game had a story full of mystery, politics, and a struggle for power in a fantasy world. The Shadow of the Erdtree story is likely to follow in those footsteps. It may introduce new storylines that tie into the existing lore, perhaps revolving around characters who have a special connection to the Erdtree. There could be a new overarching plot that involves saving or changing the state of the Erdtree, which in turn affects the whole of the Elden Ring world.
Sure, it's official. Usually, when a manga is associated with a well-known game like Elden Ring, it goes through a proper licensing process to ensure quality and authenticity.
Not that I know of. Usually, you can find out by following official announcements from the publishers or checking dedicated manga forums for the latest updates.
You might try some popular manga reading platforms like MangaDex or MangaReader. They often have a wide range of manga available, including Elden Ring.