Foxi4 Macronix EEPROM ID looks like not working. BTW, the third byte in EEPROM ID is density
10 - 512Kb/64KB
11 - 1Mb/128KB
12 - 2 Mb/256KB
13 - 4Mb/512KB
14 - 8Mb/1MB
and so on.
So it should be MX25L1001 for 128KB and MX25L4001 for 512KB save. I've never met 256Kb save EEPROM, neither Sky templates have C22212 chip ID. But I dumped with the dongle several titles EEPROM having 1 Mb (at least New Art Academy, RE: Revelations, Castelvania, Batman Black Gate, Mario & Luigi: Dream Team, Rabbids Rumble, Zelda: A Link Between Worlds) and I have no idea what should be the real EEPROM ID for that titles.
All of the above is true for Sharp EEPROM, i.e. at least 622611 and 622613 exists for 128/512KB flash size.
Several Sky templates have wrong density in card ID comparing with thr original eeprom dump, that maybe can affect save transfer from retail cards as well as EEPROM manufacturer (not sure about that, need to check, just get several saves corrupted while transferring from the retail to the sky, while others are working. That is not the encryption issue, because different SDK titles was successfully tested to transfer saves.)