This comes into factor regarding the Pokémon choices for each character as the author said that he made most choices based on personality types and appearances. This also includes some of the Kwamis and which Pokémon could accurately represent them.
Tikki as a Ledyba/Ledian is self-explanatory.
Plagg as a Purrloin/Liepard due being a black feline with green eyes.
Trixx as a Fennekin/Braixen/Delphox instead of a Zorua/Zoroark or even Vulpix/Ninetales is an interesting case, but it might be because the Fennekin line is seen under a more heroic light, likely because of Serena's Fennekin/Braixen, while Zoroark is given to Lila instead as to showcase the darker aspects of illusions and deception, even though Zoroark is usually under the Dark Is Not Evil category. But then again, Lila isn't evil, just an Attention WhoreBitch in Sheep's ClothingJerkass. In addition, Ninetales has also been given a bit of an antagonistic view due to being seen as vengeful whenever its tails are pulled.
Nooroo as a Vivillon instead of Venomoth mainly because he's based on a butterfly rather than a moth. And why Vivillon over Butterfree or Beautifly? Well, Vivillon does originate from Kalos and the name closely resembles the French word for butterfly, papillon, which is Hawk Moth's French name.
Why does Marinette seem to be more affectionate and self-conscious around Adrien here, particularly in the early chapters, than in the show? They were in school for four years compared to the one year that took place in the main show, meaning Marinette had a longer time to be around her crush. But at the same time, it was mentioned that her awkward nervousness and the classic fear of rejection made her unable to confess her feelings during those years. There's also the inner desire to make up for the less-than-ideal meeting when she thought Adrien was as bad as Chloé due to their association as Childhood Friends.
A recurring Running Gag has Marinette unable and/or forgetful to ask Adrien to exchange phone numbers, proving her inability to properly talk him early on.
Adrien being called "Ace Trainer" also references the Trainer Class in the games that are capable of providing difficult challenges for players upon encountering them in the overworld. In short, he is the biggest challenge for any Trainer to face before the Elite Four.
Even without a Ground-type Pokémon or her Pokémon not knowing any effective Ground-type moves, Marinette is still very resourceful when it came to her Lumiose Gym battle against Nadja. She had Tikki use Mach Punch into the battlefield floor to force up dirt to block Electric attacks and cover Nadja's Electric-types with it as a weak and improvised form of Mud Sport.
Luka's introduction into the story as the newest Gym Leader for Laverre City Gym after Clara Nightingale may seem like a strange choice as Clara's portrayal from the show makes her perfectly suited for the role, considering that the Laverre Gym hosts popular fashion shows for every season. However, the setting for Laverre City was written long before their debuts in the show, leaving the author to work with the little information available during the early stages of Season Two.
And there's also Luka specializing in Fairy-types in contrast to his sister's preference for Ghost-types. But then again, remember that he's considered to be Adrien's Foil. Adrien has his starter Pokémon, Plagg, a Dark-type Pokémon, and his own Meaningful Name meaning "the dark one" while Luka's name associates with lux, meaning "light" in Latin. There's also the Trainer class that debuted in X and Y called "Mysterious Sisters" that are encountered for Double Battles, composed of a Fairy Tale Girl and a Hex Maniac. These Trainer classes focus on Fairy-types and Ghost-types, respectively, serving as a suitable relationship base to use between Luka and Juleka.
What is Poison Moth's motivation behind Team Akuma's terrorism against the Kalos region? He desires the powers of Xerneas and Yveltal for a reason. Near the end of Chapter 51, he mentions not suffering the same fate as the three-thousand-year old Kalos king when Lady Ledian and Liepard Noir were cornered by his Team Akuma Grunts. From what we know of the Kalos king, AZ from Pokémon X and Y, he lost his beloved Floette in the war before ending it with the Ultimate Weapon for revenge, using it to take the lives of many to resurrect his deceased Floette. And then there's the fact that his Floette left him upon resurrection, disgusted by his actions. Does Poison Moth's situation parallel that of the king's regarding his missing wife much like how the king lost his Floette to the point that he's going through the extreme measures of finding the Pokémon entities of life and death by any means necessary?