A common trope could be the 'Power Discovery' trope. Fem Harry might discover she has some sort of connection to Poseidon's power, and as she explores this, she grows in strength. There's also the 'Underdog' trope. Despite being a female Harry, she might be underestimated at first, but with Poseidon's help, she rises above her challenges. And then there's the 'Mystery' trope. There could be a mystery surrounding her connection to Poseidon that she has to solve.
One popular trope is the 'Chosen One' aspect. In fem Harry's case, she could be chosen by Poseidon for a special quest. Another is the 'Mentor - Protégé' relationship, where Poseidon guides fem Harry in her journey, perhaps teaching her about her newfound powers related to the sea. Also, the 'Forbidden Love' trope can be used, as their different natures - a human - like fem Harry and a god like Poseidon - might make their relationship something that others oppose.
The 'Fish out of Water' trope is often seen. Fem Harry, coming from a world that's not entirely centered around the sea gods, finds herself in a strange new situation when involved with Poseidon. Another is the 'Redemption' trope. Maybe Poseidon has some past deeds that he needs to atone for, and fem Harry plays a part in that. The 'Alliance' trope is also possible, where they form an alliance to face a common enemy, like other gods or dark forces.
Chapter 347, ", I Am the Korolya Governor", is the clearest early answer because it turns Rage Owl Star's situation into a concrete plot event. The chapter turns that into something concrete by moving from Meanwhile, whether Gu Hang was capable of achieving all this still... to But those could be supplemented by the Alliance's Land Forces..
Chapter 358, ", Heart of Stone", is the clearest early answer because it turns Titans's situation into a concrete plot event. A useful checkpoint is the way the scene starts with He would solve the predicament on Korolya, which might be an even... and follows through with Human troops herded the demons toward their ultimate target....
Chapter 185, ", The goal of the war is the entire Green Valley Region!", is the clearest early answer because the buildup finally cashes out in a real clash. The chapter gives readers a real answer by opening on The vicious cycle in the Green Valley Region was not a first-time... and ending on In need of weapons, the Green Valley Region theoretically could have....
Chapter 280, ", The Voice of Fury", is the clearest early answer because it turns Anat's situation into a concrete plot event. The setup is Anat's expression became stern and tense., but the pressure keeps building through He immediately alerted his brothers in combat about the change in....
Chapter 246, ", Suburban Town Warfare", is the clearest early answer because the buildup finally cashes out in a real clash. The setup is For the army of the Luman Kingdom, the deaths and injuries of the..., but the pressure keeps building through Death was one thing, but the destruction of a Sentinel Mecha under....
Chapter 278, ", The Phoenix's Icy Fury", is the clearest early answer because it turns Imperial Navy's situation into a concrete plot event. The chapter turns that into something concrete by moving from Irong Fatches knew that she couldn't possibly stay hidden in the... to The productivity of Blackbird City had lost approximately....
Chapter 373, ", Alpha-class Psychic", is the clearest early answer because it turns Gu Hang's situation into a concrete plot event. A useful checkpoint is the way the scene starts with Those very rare individuals must be studied separately; but generally... and follows through with Lois in principle agreed that future Union taxes would be calculated....
Chapter 247, ", Charge into the Fray", is the clearest early answer because it turns Knight Titans's situation into a concrete plot event. The setup is Drex was certainly a great noble of the Luman Kingdom; throughout the..., but the pressure keeps building through And his family owned one, personally piloted by him, an Earl; you can....
Chapter 267, ", it's time once again for the much-anticipated card drawing segment", is the clearest early answer because it turns Gravity Weapons's situation into a concrete plot event. Early on, With the presence of "Spacefarers," similar tasks had become more.... By the end, We can't use it as the main force for a decisive battle, but in....
Chapter 348, ", You Must Believe in Our Loyalty", is the clearest early answer because it turns Gu's situation into a concrete plot event. The setup is A series of important strategies, he had organized them in his case,..., but the pressure keeps building through He had already thrown caution to the wind, no matter whether he might....