In this fanfiction, T'Challa's transformation into a teenage girl could start during a battle. An enemy uses a strange weapon that has an unexpected side - effect on him. As a teenage girl, he'd notice how people treat him differently. His advisors might not take him as seriously at first. He could then start to explore Wakandan life from a different perspective. He might get involved in activities that are more common among teenage girls, such as certain types of art or dance. Through this, he discovers a hidden part of Wakandan culture. He also has to face challenges like dealing with unwanted male attention in his new form. In the end, he finds a way to turn back into his male self and uses his experiences to better protect Wakanda and promote gender equality.
One possible plot could be that T'Challa, while exploring some ancient Wakandan magic or perhaps as a result of an enemy's curse, is transformed into a teenage girl. As a teenage girl, he might struggle to adapt to the different social expectations. For example, he used to be respected as a king and a strong warrior, but now he has to deal with the cattiness and competitiveness among teenage girls in Wakanda. He could also use this new form to his advantage, like infiltrating an all - female group that was previously inaccessible to him as a male. And in the end, he has to find a way to reverse the transformation and regain his true form while also having learned some valuable lessons about the different experiences of the other gender.
Well, the plot could involve T'Challa suddenly waking up as a teenage girl. He'd first be in shock, of course. Then, he might find that his skills as a fighter are still there, but he has to adjust to his new physical abilities. Maybe he tries to keep his identity a secret at first. As he tries to live as a teenage girl, he could discover new friendships. He could end up befriending some girls who are interested in changing Wakandan society in different ways. Through this new form, he also realizes how difficult it can be for girls in Wakanda, like dealing with certain traditions that limit their opportunities. Eventually, he figures out how to break the spell and uses what he's learned to make Wakanda a more equal place.