Agger was referred to sans codename in the cast list for War of the Realms: he seems to have ditched it. They called him Dario Agger: Shapeshifting CEO.

Molly can't be called Shadowcat. It's technically still Kitty Pryde's name. Besides, it doesn't match her powers.

Discord is already in use, by one of Ms. Marvel's villains.
https://marvel.fandom.com/wiki/Joshu...on_(Earth-616)

I don't expect to see the old Runaways codenames used here, so Sister Grimm and Bruiser are out.