The final identification method of cosmetics is only to detect ingredients. What can't be pulled out, even if it matches the package of the counter, as long as the ingredients are wrong, it is fake.
Generally speaking, cosmetics companies, especially large companies, will entrust different companies to produce in order to avoid shortage, which will inevitably lead to some differences in packaging. I sell cosmetics myself. I have seen many products with slightly different packaging, but the contents are exactly the same.
The best way is to go to the counter or ask someone you know to go to Korea to buy a genuine product, and then compare it yourself. If you seek authentication online, you are likely to be cheated by various businesses. They will tell you that your things are fake and then promote their own things to you.
Cosmetics can't be identified by 200% only by naked eyes. I've been selling this thing for some time, and I can tell you responsibly. I also have friends who use things for identification. I usually smell them carefully and then color them. Even so, I can't arbitrarily tell others whether it is true or not. After all, chemical synthesis is different from clothes or something. Salt and sugar look alike at first glance.
Only chemists and original product distributors can tell you the truth. The outer packaging can be copied completely, and the fake can be made more real than the real one. If you go to different cosmetics stores in Korea 10 to buy the same thing, you may buy 10 different packages. Of course, the difference I'm talking about is not that big. Generally speaking, the basic design will not change. The difference lies in the color difference of wrapping paper and the printing method of production date.
Just believe in yourself. It's tiring to be led by the nose. If you don't trust what you bought, throw it away. Find a reliable place to buy a genuine product. Otherwise, how tired.
Hope to adopt.