Notes

Gumball Main and Supporting Characters as Pokemon and Berries
Gumball Watterson = Espurr (if he didn't age) and Meowstic (if he aged) (both of them are Russian Blues)
Darwin Watterson = Goldeen (if he didn't age) and Seaking (if he aged) (both of them are common goldfish)
Anais Watterson = Igglybuff (if she didn't age) and Jigglypuff (if she aged) (both of them are desert cottontails)
Nicole Watterson = Meowstic (both of them are Russian Blues)
Richard Watterson = Wigglytuff (both of them are desert cottontails)
Penny Fitzgeralf = Stantler (Penny resembles a winged caribou while Stantler resembles a regular caribou; I can count unnatural with natural)
Gaylord Robinson = Conkeldurr (both of them resemble proboscis monkeys; some of the Muppets resemble proboscis monkeys)
Lucy Simian = Zarude (both of them are dinopithecus)
Rocky Robinson = Gurdurr (both of them resemble proboscis monkeys; go up to see why I made Mr. Robinson a monkey)
Tina Rex = Tyrunt (if she didn't age) and Tyrantrum (if she aged) (both of them are tyrannosaurus rex)
Alan Keane = Pichu (if he didn't age) and Pikachu (if he aged) (both of them resemble 1'00" jerboas; a balloon with a string resembles a rodent)
Anton = Grimer (if he didn't age) and Muk (if he aged) (both of them resemble bullfrogs; the top of a piece of bread resembles a frog's head)
Banana Joe = Nanab Berry (both of them are bananas)
Billy Parham = Cranidos (if he didn't age) and Rampardos (if he aged) (both of them resemble pachycephalosaurus; his mom's hair resembles the spikes of a pachycephalosaurus)
Bobert = Clauncher (if he didn't age) and Clawitzer (if he aged) (both of them resemble lobsters; his hands resemble the pincers of a lobster)
Carmen = Cacnea (if she didn't age) and Cacturne (if she aged) (both of them are cacti)
Carrie Kruger = Dewgong (both of them resemble leopard seals; her body resembles a seal)
Colin and Felix = Torchic (if they didn't age) and Blaziken (if they aged) (both of them resemble chickens; their lips resemble a chicken's beak, their body also resembles a chicken chick)
Doughnut Sheriff = Hippowdon (they resemble common hippopotamuses; a donut with a hole resembles a hippo opening its mouth wide)
Felicity = Rampardos (both of them resemble pachycephalosaurus; go up to see why I made Billy a dinosaur)
Gary Hedges = Stantler (both of them are moose; I can count the same species with a different animal because Stantler also looks like a moose)
Hector = Darumaka (if he didn't age) and Darmanitan (if he aged) (both of them resemble mountain gorillas; him on all fours resembles a gorilla on all fours)
Idaho = Aspear Berry (both of them are potatoes)
Jamie Russo = Bouffalant (both of them are Highland cattle)
Juke = Durant (both of them resemble red ants; a boombox resembles an ant's head)
Larry Needlemeyer = Salazzle (both of them resemble Komodo dragons; his whole body resembles a lizard; even though Salazzle is only female, I can count only one gender Pokemon in that category)
Leslie = Gossifluer (if he didn't age) and Eldegoss (if he aged) (both of them are dandelions)
Margaret Robinson = Conkeldurr (both of them resemble proboscis monkeys; go up to see why I made Mr. Robinson a monkey)
Marvin Finklehimer = Muk (both of them resemble bullfrogs; his gums resemble the gums of a frog)
Masami Yoshia = Mienfoo (if she didn't age) and Mienshao (if she aged) (both of them resemble ermines; her parents' whole body resemble weasels)
Nigel Brown = Morpeko (both of them resemble hamsters; Chris Morris, his pet hamster, resembles him)
Patrick Fitzgerald = Stantler (both of them resemble caribous; his family members' antlers resembles the antlers of a caribou but his antlers resembles the antlers of a moose, so I'm going to caribou because the cows are the only female deer species to grow antlers)
Rob = Monferno (if he didn't age) and Infernape (if he aged) (both of them resemble spider monkeys; his whole body resembles a monkey)
Sarah G. Lato = Salandit (if she didn't age) and Salazzle (if she aged) (both of them resemble Komodo dragons; an ice cream resembles a lizard)
Steve Small = Throh (both of them resemble common chimpanzees; when he took the tapes of his face in "The Lie"; he resembles a primate)
Sussie = Ponyta (if she didn't age) and Rapidash (if she aged) (both of them resemble horses; her lips resemble the snout of a horse)
Teri = Pancham (if she didn't age) and Pangoro (if she aged) (both of them are pandas)
Tobias = Numel (if he didn't age) and Camerupt (if he aged) (both of them resemble alpacas; his family members' whole body resemble alpacas but his whole body resembles a sheep, so I'm going to alpaca because in "The Slap", he turns into an alpaca in Gumball's hallucinations)