Ball and chain swinging physics?

Physics wise the swing has no bend, so you don’t necessarily need the cable component. You should be able to just link the chain up as a spline point and have it react appropriately.

If you only need this to be a visual effect, why are you wanting to leverage physics? It makes little to no sense.
sense.
a material and vector paint to define the strength of the vector offset would be a better/quicker solution.

If you need this for your portfolio and not a game asset.
add a skeleton to it. Make a skeletal mesh. Set up the phat asset and you are good to go. Much faster/better looking than both other options.
you can also animate it in blender and plug the animation into unreal for rendering, which may possibly serve you much better.