DLC Content Info

– Character All Might
– Character Biscuit Krueger
– Character Grimmjow Jaegerjaquez
– Character Hiei
– Character Katsuki Bakugo
– Character Madara Uchiha
– Character Majin Buu
– Character Meruem
– Character Seto Kaiba
– Character Shoto Todoroki
– Character Toshiro Hitsugaya
– Character Trafalgar Law
– Character Yoruichi Shihoin
– Character Giorno Giovanna
– Preorder Bonus Pack
– 3 Manga T-Shirts Pack
– 13 Manga T-Shirts Pack
– Game Logo Avatar T-Shirt
– Shonen Jump Logo Avatar T-Shirt
– P!rate Logo Avatar T-Shirt
– JUMP Starter Pack

EDIT: Tested it myself on update v3.03. All DLC characters are unlocked including bonus preorder items. Have to play the game through tutorial section till you can start picking the missions.
Lobby vehicles can be selected by pressing Dpad down. And costumes are under settings button menu-Avatar customization-Tops.