It has been a long while since Pokemon X & Y got released and most players are probably finishing up their Kalos Pokedex. As such, the players are to keep a heads up as there is a criterion that has to be met in order to complete the Kalos Pokedex.
One player, BenaCLP, warned that the Pokemon has to be bred, or caught in the Kalos region in order for it to be registered in the Pokedex. Traded Pokemon won’t be accounted for.
BenaCLP realized this the hard way. The lad claims that he has earned the Oval Charm and all the certificates. Despite the achievements, the Kalos Pokedex is still not completed. The issue appears to be with his Buizel which is traded from older gen. After breeding it, the hatchling marks the finishing line for his Kalos Pokedex.
The discovery made by BenaCLP shouldn’t be overlooked. As such, those who are pushing to complete the Pokedex might want to do some double checks every now and then.