There is a method I found that seems to work every time, I'll explain how I've come to this conclusion and then detail what to do:
First, it's already stated and known that it's pure RNG, and the base drop for Super Rare Cards is about 0,1% or 1 every 1000. But as everyone also knows, there is no such thing as a "pure RNG", there is always a code in action, and there is always a way to turn the odds in your favor (games like Final Fantasy XII have their RNG completely figured out, to a point where external programs can predict everything that will happen under certain conditions). This game is no different.
This trophy asks for all the 33 cards (4 Super Rare + 12 Rare + 17 Normal)
*For the Normal cards, just open pack normally, they will come naturally;
*For the Rare cards, use the same strategy you will to Super Rares, although you can probably skip it, you'll more than likely open at least 120 "valid" CPU chips to get the 4 Super Rares (30 to each);
*For the Super Rares, this where things get hard, but the most important part is to use Save + Reload, getting 30 Cards and then opening all to find a SR, and retrying till you get one, 60 Chips can be won by playing Quizz Millionep, 15 on Planeptune, 15 on Leanbox, and 30 on Ruins of Heart. The others are easy to get on Leanbox's first area of Vert's Route, breaking parts of every regular enemy, also easier to get if you group scouts with "Drop % +".
Now, the thing that people missed and you can test by yourself is, RNG have soft resets everytime you close the game, and that is my special little secret.
Data is : I spent 1h 45 minutes Loading + Reloading for my first SR to drop (although the method I was using was very suboptimal, but reload the game 110 times on this period, so my first Super Rare came about 3300 CPU Chips after I started (that's why there is no way this can be done without using Load + Reload). But to my surprise when I closed the game, played another game, and came back on the other day, I got my first Super Rare after 350-500 Chips (about 11 Reloads, a very tiny amount if you use the fast way of opening, every 30 Chips shouldn't take more than 25 seconds) And then my next Super Rare withing 100 Chips (3 Reloads). My luck certainly changed! Wow! But one time is a fluke, and here I was opening another 1200 Chips before my next Super Rare came. Then I decided to go play another game to keep my mind healthy and not get crazy, when I opened the game and started again, the exactly same thing happened, a Super Rare within 400~ Chips Range, and another one within 150~. Twice is a coincidence. But long story short it happened the third time, and that is a pattern by scientific definition. So yes, looks like the RNG resets every time you close the game and open another one, then come back to Megadimension, and that it's designed in a way that you get a SR on the first 500 and another on half of this interval, but this only applied for me when I literally reset and got to open the Chips, no battles, no walking, no nothing, this things could not impact in reality, but due to how RNG works on almost every other game, it might, so there is no reason to do it.
Last but not least, the way you wan't to open CPU Chips is having 6 girls under 30% HP, then using them Chips to heal them from the menu, every Chip will heal 15% Max Health, so every girl will need 5 Chips to go from Under 30% to 100%. Just open the game > Open Menu > Items (will help a lot having Chips as the first items on the list) > Use it on the girl instead of pressing the other button that is used to just open (Open will prompt a "Yes or No" box, while using to heal won't, that will make a huge difference of time on every reload). Just remember Rare and Super Rare have a special sound, making it hard to miss. But the list can be seen, sorted by New will show if you got a Super Rare or not, in case you're not paying attention while opening. Also there is no difference in rarity between the 4, some people say Blanc, some Noire, but it's all the same. I got exactly 3 Vert + 3 Noire + 2 Blanc , before getting my Neptune to end the chase, the last card can be a pain, as it's 75% a Copy vs 25% the one you need, but it's just as common as every other Super Rare so don't worry, it will eventually come. Just remember to use the tips, and you can do this with 120 or less Chips, using less than 100 Reloads (3000 Chips opened) for instance I reloaded the game the considerable amount of 600 times, due to only noticing the RNG could be tempered with from my 4th Super Rare onwards. Realistically 250 reloads should do it, due to Drops you already have. But this hardly would take more than 2 hours for the whole trophy.