Dialga and Palkia: The masters of time and space, which are conveniently two of the Infinity Stones.
Hoopa (Unbound): Thanos wants to be all places at all times, and Hoopa's hoops are the quickest way to do it!
Giratina: The master of antimatter, the one true asset that Thanos needs to bring balance back to the material universe.
Arceus: Thanos wants to be God, so of course he would have the god of Pokémon on his team!
Mewtwo: The most powerful Pokémon created by human hands, and it's purple, literally what Thanos idealizes in himself.
Luxray: It's a cat-like harnesser of electricity that fits the mental image of Wakanda's power that T'Challa honors.
Liepard: Another cat-like Pokémon, this one much darker in a way that sustains its grace, another way of depicting what Wakanda is all about.
Persian (Alolan): Also a dark-type cat Pokémon, this one depicts the "bite if approached" side of Wakanda's grace.
Pyroar: A symbol of great power and leadership that explodes in magnificent flames.
Absol: A foreseer of destruction that can warn Wakanda of disaster before the king is ready to prepare for it.
Incineroar: Following the cat theme of T'Challa's team, his signature Pokémon sums up everything about the grandness of the king, and Wakanda: they're fighters.
Toxicroak: This fighter relies on its stealth of poisonous hands to attack the enemy's weak spots, which Natasha values.
Heracross: Another fighter, it fulfills Natasha's battle strategy of using its horn to pick up the opponent and hurl it about.
Mienshao: A master of martial arts, which Natasha is as well.
Lucario: One of the most sly, ambitious fighting type Pokémon in existence, its use of auras fulfills the more distanced approach to Natasha's battle style.
Blaziken: Slightly tomboyish in looks, this ace fighter is how Natasha wants her enemies to see her as.
Greninja: Essentially, if Black Widow as a Pokémon, it would be this edgy, mysterious guy.
Mimikyu: It may seem sweet, but get under its disguise and it's a neverending nightmare. Sounds like Harley's choice of attack!
Mega Banette: She likes to use Pokémon designed to freak other people out, but she's not satisfied with that, it needs to be a SUPER freak out!
Mismagius: Not only is it a scary Pokémon, Harley also likes to use this to spy on people she doesn't like.
Salazzle: It's got Harley's sass, joy of doing bad, and is delightfully dangerous to approach.
Gourgeist: She likes to use this guy as a torture device that will driver others to madness.
Seviper: She's got a thing for snakes, for some reason they arouse her, so she imaginably likes to use this one for both her pleasure and for striking fear into others.
Jellicent: "We all float down here!"
Gengar: "Boo! Hiya, Georgie!"
Drifblim: "Don't you want a balloon?"
Banette: It'll go after you when you're young, and won't stop until you're dead.
Mr. Mime: "Excuse me sir, do you have Prince Albert in a can? You do?! Well, you better let the poor guy out! Wa-ha! Wa-ha! Wa-ha! Wa-ha!"
Blacephalon: It's a clown, its head explodes, it's a ghost, need I say more? It's born to torture children.
Garbodor: For all we know, Shrek may see the garbage Pokémon as a tasty snack...
Skuntank: I hear that ogres see smelly Pokémon like this one as great cologne.
Muk: It's got the same cosistency as Shrek's earwax and boogers, and the jelly he puts on toast.
Exploud: If he needs somebody to GET OFF HIS SWAMP, but needs to shout from afar to do so, this guy will get the job done.
Victreebel: These are exactly the types of creatures you'd see in a swamp like the one Shrek lives in, and the ones you wish didn't live there.
Swampert: Besides just having the word "swamp" in its name, Swamperts are like ogres: they have lairs.
Politoed: This guy has the most fun with SpongeBob's pet snail, Gary.
Dewgong: Not much to be said, it's just cute!
Primarina: SpongeBob loves to sing duets with his signature Pokémon... while playing the mayonnaise!
Azumarill: A cute, playful little critter, it's the definition of F.U.N.!
Simipour: SAlso incredibly playful, this Pokémon creates fun whirlpools and waterballs... even though it's already underwater! (SpongeBob logic FTW!)
Corsola: SpongeBob keeps this one handy, as pioneers used to eat them (or at least their appendages) in times of hardship.
Persian (Alolan): A symbol of high sophistication, this is an ideal White House pet for someone who wants to be powerful and ruthless.
Gumshoos: They have the same hairdo, they both have tiny hands, they both want to e-Raticate a single race with black moustaches, so the shoe fits!
Braviary: Literally the symbol of America: a red, white, and blue eagle!
Gyarados: No better way to control borders around the oceans than an army of these ill-tempered beasts!
Haxorus: A ferocious monster that can easily destroy anything, the perfect bodyguard for Trump!
Any Ultra Beast: Beyond just Nihilego, a vivid mind controller for wicked thoughts, literally any other Ultra Beast fits Trump's persona exactly.
Florges: This is the only efficient way to care for all the flowers that grow around the White House.
Tsareena: It's a symbol of queenly authority, an image of tremendous beauty, who else but Melania Trump to try and promote that to US women everywhere?
Aromatisse: Yes, I know I got its name wrong in the image... but this Pokémon is literally all about perfume, which keeps Melania looking twenty years younger!
Roserade: It's just like how the First Lady should be: beautiful to look at, but don't touch! That, and it provides Melania with some lovely decorative roses.
Ninetales: It's just a beautiful sight to accompany her in her walks outside of DC.
Pheromosa: Her husband has access to every Ultra Beast out there, and her one of choice is the one that's already an image of beauty, even if it's seen as a pest... kinda like how Donald sees most foreigners.
Pachirisu: Just like old Peapod, this little squirrel loves to hang out in Bob's shirt pocket and watch as he paints!
Smeargle: "You can make reality whatever you want to make it on this canvas," which in Smeargle's case is what its moveset will be.
Swellow: Bob loves those beautiful birds that create soft sounds that paint the environment.
Furret: It's very playful, charming, and a cute little devil, who else but Bob would love such a rascal!
Gogoat: It's the perfect choice of ride when going on a casual excursion throughout the woods that inspire Bob's imagination.
Sawsbuck: It's the Pokémon of the four seasons, which fire Bob's paintings with all its happy little accidents!