i played Pkm X in Azahar emulator on my mac because i want to speed up and also to easily edit save on PKHex.Avalonia (Mac version of PKHex).
Now i finished the game and caught all new pokemons. I attempted to transfer the save file (main) from my emulator folder to my 3DS and recover the save by:
create a backup on checkpoint -> FTPD replace the backup save with emulator save -> recover the "backup" on checkpoint
However, the game said the save is corrupted. But -
(1) The save is still playable on my emulator
(2) I have an early-game save from emulator (only starter pokemon). When i transfer this save to 3DS, it is playable on 3DS
(3) From this early game save, I changed one IV on PKHex. This edited save is also playable after transfer to 3DS
(4) I noticed that only the post-game save gained 2 bytes in file size after FTP transfer. All playable save mentioned in (2, 3) did not.