Temporarily, I mean.
Like all long running super hero series do.
I'm not talking about a teen Moon Knight replacement or anything like that.
But like an adult replacement that's crazier and more deranged than Marc, to show that in the end, it's best that Marc is Khonshu's chosen one as Moon Knight, and nobody else.
Like when Azrael replaced Batman, or Dr. Octopuss replaced Peter Parker.
You'd think with so many of Marc's enemies having the M.O. of trying to replace him, like Shadowknight or Black Spectre, this would have happened already.
He's also had about a zillion reboots and series, whereas Batman, Iron Man, etc, are characters who have had long-running series. I think that what holds true for Moon Knight holds true for the Silver Surfer and Alpha Flight, they keep trying to give these guys series, it never really takes.