I watched a simulation of the binary black hole merger of 2019 April 12
When the "apparent horizons" (their terminology; are those different from event horizons?) touched, the two combined and the merger was complete. So I'm wondering: would it be possible for two black holes to quickly pass by each other, so that their horizons briefly touched, but then they continued on their ways separately.
PS: The video was nice, but I would have preferred it stay on a 2D plane. I don't know if the changing points of view was done by the animators, or if the two objects really did move around in three dimensions.