Since there's a lot of people that seem to not know what VGN-items only consist of, here's a general list:
Pets, Pet Skins, Pet Data Chips
With Costumes, Pet Skins, and Bikes, you can request only those that have been released and are not special holiday costumes
This means that most costumes/bikes/pets and petskins come from Mystery Boxes, which count as VGN items.
Literally anything shown in Item Mall
Items that won't be accepted:
In-game gear, such as armor, weapons, accessories (trinkets, earrings, rings), jewels, etc.