Given that Kingpin and Moon Knight don’t often cross paths in the comics, an appearance by that character seems less likely than the actor filling in a new role.
Screen Rant will keep you updated on any Moon Knight news as it becomes available.
There’s definitely a lot of positives to bringing the actor on board any potential Moon Knight as the character of Kingpin, the biggest being that it could help sell the project to any unfamiliar with the character of Moon Knight or his comic history.
It’s admirable that D’Onofrio is so committed to the MCU and finding ways to expand his role there.