Your challenge is to have Atenism experience a revival at some point after its decline. It doesn't necessarily have to become the state religion again, it just has to have a significant following.
Was it ever popular, or was it just Akhenaten enforcing the faith under penalty because he's a hipster who liked monotheism before it was cool
There was a great timeline going some 5 or 6 years ago focused on this...except, as is necessary I think, you can't really have Atenism be "revived" after it fades--it has to continue. I suppose if it did continue several generations or more, then got discredited or abandoned somehow, it would have deeper grassroots as it were and be more likely to persist in eclipse and thus have potential to be revived and come back.
But the problem was it was a two generation wonder, with one of those generations being darn short, and failed to be deeply founded enough to persist.
For the TL that took on this challenge:
The Realm of Millions of Years
Some unwise person broke the no-necromancy rule and got the thread locked--half a decade ago. The author is still around though not terribly active, but I doubt they want to dive back into this story again. Shame, it was great while it lasted!