If you are building your own private emulator (like a custom PUBG server), you can choose your own AES key. But this has nothing to do with Krafton's official servers.
You find a file or a text document that looks like this:
AES_KEY=0x4D, 0x5F, 0x7E... "Full Key Here!!"
Result: This is 99.9% guaranteed to be an outdated key from a PUBG build released in 2018. It will not work on the current live servers. Using it will simply return gibberish data. pubg aes key full
Krafton uses a hardware ID (HWID) ban system. If you are caught modifying network encryption or game files, they ban your Motherboard, Hard Drive, and CPU serial numbers. Buying a new copy of PUBG won't work—you need a new PC. The Truth Behind "PUBG AES Key Full": Security,