The principle for destruction via a gunshot or a sword slice is the same. You need to figure out how and when to spawn a PhysicsField actor near or inside the destructible mesh to trigger the destruction of that mesh.
However, in the case of a sword slicing destruction, you would need to also figure out a solution of how the mesh is broken down using the path the swords slices through (probably dynamically create 2 meshes based off the “sliceResult” and separate them)