The development connection

Xbox Wire describes Section 9’s founders as former Tarsier leads who worked on Little Nightmares. That connection explains the comparison; it does not make End of Abyss a sequel or part of the same fictional world.

What changes for the player

Comparison based on official description and Xbox Wire’s preview
QuestionEnd of Abyss evidenceComparison boundary
Can the protagonist fight?Official description includes combat and gear upgradesDo not expect identical helplessness
How is exploration organized?Branching paths, tools and backtrackingDo not treat it as the same route structure
Is it a sequel?A separate Section 9 productShared developer history is not story continuity

Which experience to choose

Choose based on how much active combat and backtracking you want. If you mainly want cinematic atmosphere, watch a gameplay segment before assuming this game matches your expectations. This is a conditional recommendation, not a rating of either game.