The easiest way to check if the antirollbar bushes have gone is to remove one drop link and go for a drive if the noise has stopped its the antirollbar bushes.When they have even modest wear the banging can be annoying, almost as annoying is the fitting proceedure.
There is that method but still flawed in eliminating one or the other.
Once you disconnect the drop links, you eliminate them rattling too as they aren't under tension so no longer can a worn ball joint rattle either... So you are still left with two possibilities.
Thankfully though a pry bar against the AR bar and the bottom drop link ball joint while holding the top drop link can usually give and indication if there is a click felt lifting it up and down with the pry bar.
Then disconnect them, if the rattle is still there.... It is definitely the bushes then.
Especially if you can grab the AR bar and pull it towards you and push it away laterally with mild pressure.
One last thing to consider before rushing out to but new bushes.
If you can do that, it may be worth changing the AR bar with the bushes complete... The paint and metal below the bush has worn enough so just fitting new bushes would only alleviate the rattle symptoms for a week or two until it returns with vengeance, so false economy given the difficulty in replacing them when it takes slightly less effort to replace the bar with new brackets and bushes.