One common theme is redemption. Bucky has a complex past and Tony often has to come to terms with that. Another theme is friendship. They are two very different characters but in fanfic they often find common ground and become friends.
One possible scenario in this fanfic could be that Bucky and Steve notice Tony is overworking. So they start by making sure he eats regularly. Steve might cook his old - fashioned but hearty meals, while Bucky keeps Tony company during meal times to make sure he actually eats. They also likely limit his access to the workshop for a while, to force him to rest. Maybe they set up a little relaxation area in Tony's living quarters with comfortable chairs and soft music.
Healing is another common theme. Both characters usually have their own emotional wounds. In these fanfics, through their relationship of adoption, they help each other heal. For example, Bucky's stability can help Tony deal with his insecurities, and Tony's intelligence and humor can help Bucky come to terms with his past.
The theme of friendship also runs strong. As Bucky protects Tony, they start to form a bond that goes beyond just protection. They become friends who support each other through various difficulties. Additionally, there's often the theme of sacrifice. Bucky is willing to put himself in harm's way to protect Tony, showing his selfless side.
One common theme is the exploration of identity. Since Tony is female in these fanfics, it often delves into how this change affects her relationship with Bucky and her place in the Marvel universe. Another theme is redemption. Bucky, with his complex past, often goes through a journey of redeeming himself in the eyes of fem - Tony.
One great 'bucky fem tony strak fanfic' is 'The Unlikely Alliance'. It explores the complex relationship between Bucky and Tony in an alternate universe where Tony is female. The story is filled with action and their banter is really engaging.
There could potentially be a 'tony bucky sex powered alien ship fanfic' out there given the wild and creative nature of fanfiction. But it's not a mainstream or well - known type of fanfic. It might be something that a very small group of fans with very specific interests have created. Also, due to the nature of the title, it might not be suitable for all audiences or all fanfic platforms, which usually have content guidelines to follow.
The theme of forgiveness is also prevalent. Given their history, with Bucky being involved in the death of Tony's parents, forgiveness is a big part of their relationship in fanfics. Some stories show how difficult it is for Tony to forgive Bucky, while others show how Bucky tries to earn that forgiveness.
One common theme is protection. Bucky and Steve often see Tony as someone who needs safeguarding, whether it's from physical threats during missions or from the emotional harm caused by his past. For example, in many fics, they'll stand up for Tony when others in the Avengers question his motives.
One great 'bucky and steve care for tony fanfic' is 'Healing Hearts'. In this fic, Bucky and Steve notice Tony's struggle with post - battle trauma. They start by simply being there for him during his nightmares, bringing him warm milk and sitting with him until he calms down. Their care gradually extends to helping him in the lab, understanding his projects, and protecting him from those who might want to harm him for his tech.