It depends. If they don't violate copyright laws and are not for commercial purposes, they might be okay. But if they copy official content without permission, it's likely illegal.
Well, it could be that the creators want to explore themes like loss, friendship challenges, or the difficulties the Pokemon face. These sad elements can add depth and make the comics more relatable and thought-provoking.
Fan-made Pokemon comics usually have a lot of imagination. They could feature cross-over with other franchises, or explore the backstories of lesser-known Pokemon. The level of detail and the depth of the world-building can vary greatly depending on the creator's skills and passion.
There aren't any. The Pokemon world is focused on adventure and friendship, not such inappropriate content. Such comics would go against the nature and values of the Pokemon brand.
No. The Pokemon fan community generally values the family - friendly and positive nature of the franchise. Sexual fanfiction goes against these values and is not acceptable. It can make many fans uncomfortable and can also damage the reputation of the overall community.