Spider-Man: Homecoming - 7 Possibilities For The Secret Character
3. Shocker (Either Of Them, Really)
Why It COULD Be Him
He probably fits the context of the LEGO set more than most of the suggestions on this list: especially as there's a pretty big hint that the gauntlets we've already seen teased in the trailer are based on recovered Chitauri tech.
The Shocker gang have long widely been considered a criminal heist gang, and them stealing from the DODC to recover artefacts from the Battle Of New York would be the easiest narrative solution to The Tinkerer getting his hands on the technology. And maybe he's just greyed out as Marvel want to preserve the look of the character?
Why It Might Not Be
Why would Marvel be so careful to hide one first look at him and plaster another one quite liberally across the Toy Fair? It wouldn't make sense unless it was a blanket rule. And who says he's even working with Vulture?