The dumbest part about the pressure kirby, is that you can change it for the situation:
Say a person is playing H groove, instead of using 2A-B-C-6C you can use 2A-6C to throw off their timing, not only that but it throws them into a situation where they are doing HIGH-LOW-HIGH-LOW which most players will focus on blocking more than shielding or back dashing, and it still chips guard as fast. Plus, they are doing the high lows because you can charge 5 other moves that could either be high or low, because that is necessary. I would like to add that her Arc Drive has a frame of super armor...... I think, I was going through a bunch of different characters moves at LK's place. Also, from the testing I saw F-ries having massive clash with her 2B, not sure if that works on everyone, but I did it to at least 10 different characters aerials.
Another trick I noticed for her pressure, is a bunch of people will sit and watch what you are doing, so instead of continuing the pressure with x move, you can just hop forward and grab because the person is so focused on blocking. A lot of people will backdash, just continue the 2A - B - C - 6C, it will hit them even if a move whiffs, just be careful with her, eventually you can do charge mix ups and if a move whiffs you'll get punished because you are stuck in the charge animation.
If a person is shielding you a lot here is a good tip, just do one rep of 2A-B-C-6C, then jump when you expect the shield and come down with a JC. If they start shielding that JC, and are not in H groove, just block afterwards. If they are in H groove whiff the JC with the animation still coming out, and continue with pressure.
The biggest part about these "gimmicks" is making the person think you are going to do the reps of 2A-B-C-6C again, but you really don't have to, you could even just block after the 6C or back dash there are plenty of options she has.