A time traveling Danny Phantom as Kronos Pariah Dark as Uranus Clockwork as Khronos
Clockwork isn’t Kronos, he is Time itself, but Danny as Kronos, as his champion/Avatar and able to time travel without any consequences.
Danny did travel into the past to fight Pariah Dark again, while he was still Uranus. And after a few years of living with the Titans, Cyclops and Hekatonchiere, he left to kill/defeat Uranus and just left.
During that fight against Uranus, Danny kind of broke off a few parts of his Essence. Pariah Dark Alive was just as strong when he was a Ghost.
The Olympians are created similar to how Akatosh creates the Dragons. They were part of him, kind of like his Essence that broke off him, mirror-shards if you will, that Rhea did fuse with her own.
Danny never did marry Rhea, just left from his Essence and shards left behind as he did time travel again.
Rhea used those mirror-shards to create her six children out of the seven shards. She did find 6 and the last one was found and used by a Philyra, the Nymph/Oceanid, which kind of angered Rhea.
Till modern times, the OG Olympians never met Danny/Kronos. They did feel their father a few times in history, but never truly met him at all.
But the 7 later meet their Sister Dani/Ellie.