Direct answer
Memory echoes are named in official world material, but their precise player-facing mechanics are not yet fully explained. The term should not be expanded into invented collectibles or skill trees.
What is not confirmed
This answer is intentionally limited to what the cited primary source establishes. It does not rely on fan-maintained lists, retailer placeholders, edited trailer cuts, leaks, or assumptions imported from other action RPGs.
How this answer will be updated
The page will be checked after the dedicated summer State of Play, material store-page changes, and the retail launch. New details will be added only when they answer this exact question; separate search intents will keep their own URLs to avoid overlap.
Primary source
Official Steam page, last checked July 31, 2026. The linked gameplay hub provides the surrounding guide context.