Maybe it starts with fem Harry accidentally ending up in Wakanda. She and T'Challa initially clash due to their different cultures and ways of doing things. But as they get to know each other, they discover a deep connection and start to fall in love. Along the way, they have to deal with opposition from some in Wakanda who are skeptical of an outsider being so close to their king.
There are many fanfiction platforms where you might find such stories. Try Archive of Our Own (AO3). Just go to the site and use the search bar to type in 'fem harry is the mate of t'challa'. It has a vast collection of fanfictions, and you're likely to discover some great reads there.
One possible plotline could be that fem Harry initially resists the idea of being Orm Marius's mate. Maybe she has her own goals and dreams that she thinks being in this relationship will interfere with. But as time goes on, she starts to discover new aspects of Orm Marius and gradually falls in love.
A third plotline could center around the challenges they face as a couple. There could be opposition from both their respective worlds. In Harry's world, the wizarding community might not understand her relationship with a non - human from another realm. In Sesshomaru's world, demons might have their own opinions about a human - like Harry being his mate. This could lead to many conflicts and a journey of them trying to be together despite all the odds.
Another theme is the idea of power. Both Harry Potter (even as a female version) has her own magical powers, and T'Challa has the power of the Black Panther and the leadership of Wakanda. Fanfictions might explore how they use their powers together, or how their different understandings of power can either clash or complement each other. For example, in some fanfictions, they use their combined powers to face a greater threat that neither could handle alone.
One possible plotline could be the two characters starting as enemies or at least with a lot of misunderstandings. As the story progresses, they gradually come to understand and trust each other, and a romantic relationship begins to form.
Well, in a 'fem Harry is a Queen fanfiction', a plotline could be that fem Harry dreams of Queen and in her dreams, the band members give her advice on how to deal with Voldemort. This then gives her the strength and new strategies to fight against the dark forces. Also, it could be that she discovers a hidden connection between Queen's music and ancient magic that only she can unlock, leading to her becoming a more powerful witch.
One possible plotline could be that Harry discovers his unique connection to Severus and Lucius and has to deal with the secrecy and the implications within the wizarding world. There might be a lot of internal conflict as he tries to understand his feelings for both of them while also facing the judgment of others.
One possible plotline is that they are all framed for a crime they didn't commit. To clear their names, they must team up. Harry's quick thinking, Snape's ability to deceive when needed, and Lucius's connections all play a part. As they work together to find the real culprit, they form a bond of mutual trust and respect, which is the foundation of their new - found mate - ship.
A possible plotline could be Harry's struggle with his new vampire identity. He might have to hide it from his friends at first. And Snape, being his mate, could be the only one who truly understands what he's going through. Another plotline could be the two of them facing opposition from the wizarding community because of their unusual relationship.
One plotline could be that fem Harry discovers a hidden connection to Morgana through her magic. Maybe she has some latent powers that are related to Morgana's, and she has to explore this connection to understand more about herself and her place in the magical world.