Moon Knight took a deeper dive into Egyptian mythology than we ever expected, but Marvel Studios failed to take the opportunity to make reference to Rama-Tut. A Kang the Conqueror Variant, this Nathaniel Richards travelled back in time and ended up ruling over Ancient Egypt with advanced technology from the 30th Century after getting trapped there; and yes, he crossed paths with Khonshu!
There's every chance Rama-Tut is being saved for a future Moon Knight project (after all, we're not expecting to learn more about Kang until Ant-Man and The Wasp: Quantumania), but he was very nearly referenced in the Disney+ series. Head Writer Jeremy Slater confirmed as much while taking to The Direct, and it actually sounds like a scene may have been shot at some point.
"There was a line in the script, and I don’t know if it survived. I can’t remember. But there was a line where, I think Steven, is sort of rattling off some Egyptian history that he has locked away in his brain, and he did mention Rama-Tut," the writer confirmed. "I don’t remember if that scene, if that line is still in the show. But it was that small, it was him mentioning a list of famous pharaohs."
Sadly, we can confirm that Rama-Tut wasn't mentioned in the show, and there has to be a reason for that. It would be strange for this particular Kang Variant to not make his presence felt somewhere down the line, but given the complicated nature of time travel and the Multiverse, it's possible he hasn't travelled back in time yet. We're relying on the Ant-Man threequel and Loki to clear things up.
As for Moon Knight, Marvel Studios still hasn't announced a season 2 or feature film continuation. The character's story is bound to continue in some form, though, especially after that big cliffhanger.