theSLAYER

A repository for random distribution devices used across the years.
Quick rundown of the images that we have presently

Gen 1 (VC)
UK VC Mew Redemption (and Save Restore screen on the distribution device!)
JP VC Mew Redemption

Gen 1 & 2 (Retail)
Toys R Us security sealed Mew Cartridge and Gameboy
Mew and Celebi Machine (and article)
Spaceworld Mew screen (has different sprite than standard Mew)

Gen 3
Pokémon Day 2004, Germany - Multilingual selection screen (Eon Ticket?)
Aura Mew Distribution Device
10ANNIV/10 ANIV Distribution Device (Groudon GBA SP and Yellow GBA SP)
Pokémon Festa 2005, Japan - Festa Metang Device and Redemption
Mystic Ticket Distribution, Japan
European Shiny Zigzagoon
Old Sea Chart Redemption (device can't be seen)
Gen 4
Crown Entei (Slot 2)
Regigigas Redemption Video (Slot 2)
Battle Festa, Diamond - Magmar (Slot 2)
10TH Deoxys (Slot 2)
Misc. Distribution carts (User YoshiMoshi's collection photograph)

Gen 5
Misc. Distribution carts (User YoshiMoshi's collection photograph)
Gen 6 & 7
Various distribution 3DSes:
Movie 18, Korea
PC Birthday 2017, Japan
Pop-up Store Charizard, Korea
WCS Mew, Korea
Eevee Friends, Korea
Melemele Shiny Tapu Koko, Korea
Worlds18 Meloetta distribution relay

When you select Scan QR Code from your in-game menu, you can register Pokémon as Seen in your Pokédex.
Players can go to their registered Pokédex Entries, to share QR codes for other players to scan.

However, for certain Pokémon, when you try to generate a code in-game, it'll give the "This is a special Pokémon. There is no QR Code." message (as seen below).

This album hold such entries. Their QR codes were scanned from Japanese Ga-olé disks, which was marketed as being able to be scanned into SM and USUM. However, these QR codes are region locked to JP consoles only.