What we have here are passwords for Pokemon Conquest which you can use to unlock rare pokemons. To enter the codes, press start on the Ransei map or tap menu and select the option password. However, you can only unlock these pokemons after conquering your fifth kingdom. They appear after the next in-game month after you enter the password somewhere in your kingdom.
The following are
Pokemon Conquest passwords with their corresponding unlockables (US version).
Sr5Z5GqAgR - Dratini
2rz3XFCKmR - Eevee
GfV33RVN3F - Lapras
Jnm3kqgN8X - Emolga
LTb3n3RYJ8 - Gible
mq2xRVNgRL - Gyarados
frCLRpXG88 - Oshawott
CNZF3wpq3x - Panpour
niE33w9rwM - Pansear
FZP8GqRZRR - Pikachu
Shw8mxRAJR - Riolu
8GV3LMGrnM - Scyther
Meanwhile, here is a good video explaining where to put the passwords in Pokemon Conquest US version.