The asset in question is Creating Portal To Another Reality by Zegi.Assets, specifically designed to create worlds that differ in minor details such as materials from the original one. Perfect for puzzles and abstract games, it's based on the function of the material, not on Render Targets with Scene Capture, and doesn't feature actual teleportation with the objects only changing their properties. You can make an unlimited number of portals.
Creating Portal To Another Reality comes with Blueprints, full documentation, and supports Unreal Engine 4.18 – 4.27, 5.0 – 5.3 for both classic mode and VR. The latest update even lets you carry a portal around like a mirror!