Entanglement between two evaporating black holes

We study a thermo-field double type entangle state on two disjoint gravitating universes, say A and B, with an eternal black hole each. As was shown previously, its entanglement entropy of the universe is computed by generalized new spacetime constructed suitably gluing holes B. such gluings when universes are asymptotically flat AdS cases, especially masses these different. also clarify rule to construct glued in more general settings from gravitational path integral view point.