Leaker iFireMonkey mentioned today that the next My Hero Academia collab will feature the characters Dabi, Shigaraki and Himiko Toga!
He released 2 images showing the characters and extra cosmetics, but so far there are no ingame images wirth characters.
So the 3D models could probably have come encrypted (and then the assets are decrypted when they are released in the store), or the collab could just come in another update in next weeks.
Several characters from My Hero Academia are already available in Fortnite and appear from time to time in the item store: Deku, Uraraka, All Might, Bakugo, Mina Ashido, Shoto Todoroki and Eijiro Kirishima.
Remembering that Fortnite also always has new collabs with anime, and soon we may have a Jujutsu Kaisen one, with the characters from Jujutsu Kaisen 0: Yuta, Maki Zenin and Panda. For now, the collabs still don’t have a release date.