Is Ned a comic character or one made for the movies? Also they can do Mary Jane but not Michelle. Jason
The two "Marvel" Spider-man films are legally very much Sony movies. That means all characters in them belong to Sony. With the exclusion of special guests(tm) Tony Stark, Nick Fury etc.
But every character that appeared first in these movies - say, Michelle - is owned by Sony. Sony also owns "Mary Jane", as it's a Spider-Man character. That means changing her name to "Michelle" really only was an artistic choice. A nod to the comics, while still seperate from the comics or the Sam Raimi movies. Kevin Feige loves that, because it allows for more interesting and unpredictable stories. But Spider-Man was very mucch a work-for-hire by MARVEL for someone else.
The only thing that's iffy is weather or not Sony is allowed to name-drop "Tony Stark" or "the Avengers" going forward. They sure as hell aren't allowed to introduce more MCU elements (like namedropping Cpt. Marvel), or have more appereances (by, say, Happy Hogan). But Stark and the Avengers have been integral parts of the first two movies - which, again, are owned in their entirety by Sony. So there is very likely a special contract clause for this specific case (MCU elements that have already appeared on Spider-Man). But none of us knows the specifics.