At the end of Eternals, Dane makes a cryptic reference to his complicated family history” which is explored further in one of the post-credits scenes. Dane nervously paces before opening a box containing a sword wrapped in bandages. He reads the inscription carved into the lid and translates it out loud – “death is my reward”. Then he says, “I’m sorry, I have to try”, but who is he talking to when he says that? Is he apologising to himself for risking death to touch the sword, or is communicating with his mysterious ancestors?
Whatever the case, Dane’s family history wouldn’t have been referenced if it wasn’t going to be explored in the future, so I think we can expect this storyline play out some time in the MCU.