Distributing these keys is illegal as they are proprietary Nintendo property. The only official and legal way to obtain them is to dump them from your own 3DS hardware using a tool like GodMode9 : : Install GodMode9 on your modded 3DS.
: ~/.local/share/citra-emu/sysdata or home/.var/app/org.citra_emu.citra/data/citra-emu/sysdata macOS : ~/Library/Application Support/Citra/sysdata citra aes keystxt work
For Citra to recognize the keys, the file must be placed in a specific subdirectory within your Citra user folder called . Distributing these keys is illegal as they are