This is my list of main characters:
Baby Bowser
Baby Daisy
Baby Luigi
Baby Mario
Baby Peach
Baby Rosalina
Baby Wario
Balloon Baby Yoshi
Banktoad
Birdo
Blue Sprixie Princess
Blue Toad
Boom Boom
Boss Sumo Bro
Bowser
Bowser Jr
Bubble Baby Yoshi
Cappy
Captain Toad
Chain Chompikins
Cyan Sprixie Princess
Dr Luigi
Dr Mario
Dry Bowser
E Gadd
FLUDD
Glowing Baby Yoshi
Gold Mario
Goomboss
Green Sprixie Princess
Hariet Broodal
Hint Toad
Honey Queen
Iggy Koopa
Jumpman
Kamek
King Bob-omb
King Boo
King Lakitu
Koopa Kid
Larry Koopa
Lemmy Koopa
Lubba
Ludwig von Koopa
Luigi
Luma
Madame Broode
Magic Paintbrush
Mailtoad
Mario
Meowser
Metal Luigi
Metal Mario
Mii
Morton Koopa Jr
Nabbit
Noki
Orange Sprixie Princess
Paper Mario
Petey Piranha
Pianta
Pink Gold Peach
Plessie
Polari
Poltergust 3000
Poltergust 5000
Pom Pom
Princess Daisy
Princess Peach
Princess Rosalina
Purple Sprixie Princess
Queen Hisstocrat
Rango Broodal
Red Sprixie Princess
Roy Koopa
Shadow Mario
Silver Luigi
Spewart Broodal
Tiara
Tired Yellow Toad
Toad
Toadette
Toadsworth
Topper Broodal
Waluigi
Wario
Wendy O Koopa
Whomp King
Yellow Sprixie Princess
Yellow Toad
Yoshi