If you are looking for QR codes to "inject" specific Pokémon directly into your existing save file (often called the "PCHex" or "Web Browser" exploit), be aware that this method only works on very old 3DS firmware versions (9.5.0-22 or lower).
Naturally, he scanned it immediately.
: The modified files are then played on an emulator like Citra or on a 3DS via the Luma3DS layeredFS feature. pokemon y randomizer qr code