Linked Chest is a different kind of ender chest. Instead of allowing personal access to an inventory from any location, it allows items access to a linked inventory from any location.
Items in the first 9 slots of a linked chest are considered “linked”. If you pick that item up from anywhere, it will be transferred into the first available slot in a linked chest that links that item.
To make a linked chest, you need 3 Ender Pearls, 1 Gold, 1 Lapis Lazuli, and 1 normal Chest. The recipe is shapeless.
Hold shift (sneak) while picking up an item to bypass the link and pick up the item yourself.