I think I may have just found a new tactic for Kirby. It's a bit tricky, and kind of hard to explain, but I'll try my best.
This is just a new way to effectively recover when hanging from the ledge. If the opponent is somewhat close to the edge, this should work no matter whether they shield or not. All that's involved is letting yourself fall just a little bit further before ledge-hopping, and as soon as you jump to cancel the falling, hold towards the stage and use the hammer. When the hammer is used before reaching the apex of a jump, it doesn't give that extra little float that you would normally see. If you do it right, you should barely go over the lip of the edge while using the hammer, and hit the ground while the attack frames of the hammer are in front of you. Landing while the attack is still in motion gives no additional frames of lag, and the shield lag given from the hammer should keep the opponentin the shield until you can attack again. I've tested this in AR, and the hammer shield lag is 18~ frames, while the Kirby's actual landing lag is 24~ frames. As something to compare it to, that's pretty much the same time it takes a Kirby to wavedash. Most characters have at least 5 frames of lag before the grab hitboxes appear, and adding on 4 or 5 frames of player error before starting the grab should give Kirby enough time to crouch, thus avoiding the grab, and start a dtilt to knock them back. And this is assuming that the opponent saw this coming and has practiced against it. In most cases, the Kirby should have enough time to attempt a grab himself before the opponent will react.
Again, it's probably hard to imagine without actually seeing it, but I've tried my best to explain it. I haven't practiced this against a human opponent too much yet, but it should theoretically it will work great.