Yes, there are some really interesting 'Harry Potter Sellsword Fanfiction' out there. You can start by looking on some popular fanfiction websites. Some of them might be hidden gems that combine the magical world of Harry Potter with the concept of a sellsword in really creative ways.
The unique part about 'Harry Potter Sellsword Fanfiction' is the combination of two different concepts. The magical world of Harry Potter and the idea of a sellsword, which is more common in medieval or fantasy settings outside of the Potterverse. It creates a new perspective within the familiar wizarding world.
One common plotline is a sellsword becoming involved in the power struggles between the great houses. For example, they might be hired by one house to spy on another and end up getting caught in a web of political intrigue.
You can try fanfiction websites like Archive of Our Own (AO3). It has a large collection of fanfictions from various fandoms, including 'Game of Thrones'. Just search for'sellsword' in the 'Game of Thrones' section, and you'll likely find some interesting reads.
One possible plot could be that Harry uses his skills from fighting Voldemort and his knowledge of the wizarding world to form a sellsword company. He might recruit some of his old Hogwarts friends like Ron and Hermione. They could offer protection services to wizarding families or even to magical creatures. For example, they could protect a family of centaurs from poachers. The company could also get involved in solving magical disputes in a more hands - on way than the Ministry of Magic usually does.
His first recruit could be Neville Longbottom. Neville has proven himself to be brave and skilled in magic, especially after his growth during the Battle of Hogwarts. He would be a great asset to the sellsword company with his knowledge of herbology, which could come in handy for making potions for protection or healing in their missions.
There should be no sex content in kids' cartoons. The industry has strict guidelines and standards to protect children from such inappropriate themes. Cartoon creators are well aware of their responsibility to provide innocent and educational entertainment for kids.
I think having a clear theme and a good understanding of the topic you want to convey are essential. Also, strong drawing skills and the ability to use humor or satire effectively can make the cartoon stand out.