Love against all odds is a prevalent theme. Since Sasuke has his own goals and a somewhat dark past, the OC usually has to overcome many obstacles to be with him. It could be his own emotional barriers or external threats. Also, self - discovery is common. The OC often discovers her own strength and purpose while being with Sasuke, like in some fanfics where she becomes a stronger ninja through her relationship with him.
A good fanfic should have well - developed characters. It should show Sakura's strength, not just as a medic - ninja but also as Sasuke's wife. Her determination and love for Sasuke should be palpable. For Sasuke, it should show his growth in terms of his relationship, like becoming more expressive. The story should also have an engaging plot. Maybe it involves a mystery or a new threat to the ninja world that they have to face together.
Another common theme is the adjustment to the Naruto world. Since the oc wife is an original creation, she has to adapt to the unique culture, powers, and politics of the Naruto universe. This often creates interesting plotlines as she tries to fit in while also being with Sasuke.
As a fan of online literature, I don't have the experience or knowledge to answer this question. However, according to the online novel resources that I know, I can search and check the plot of Naruto: My Wife Is Sasuke to find a novel that is similar to the plot. However, please note that due to the wide variety of online literature works, it may not be easy to find completely similar or identical plots.
There could be Naruto. Since he and Sasuke have a strong connection in the original series, he might also be involved in the gamer fanfiction, maybe as a rival or teammate in the gaming world.
He might meet the future versions of Naruto and Sakura. Their relationship with him could be very different in the future, perhaps they are now leaders of the village and Sasuke has to adjust to their new status.
One common theme is role reversal. It flips the traditional dynamic between Naruto and Sasuke, which makes for an interesting exploration of their characters. Another theme is the exploration of family and domestic life. Since Naruto is in the role of Sasuke's wife, they often have to deal with things like running a household, which is a big change from their usual ninja adventures.
Naruto is often paired with Sasuke. Their bond is so strong that in post - war fanfictions, they are usually shown working together to rebuild the shinobi world. Sakura is also a common character paired with Sasuke. Since she has feelings for him, in these fanfictions, she might be trying to get closer to him and help him heal from his past traumas.
Sakura also often appears. She might be confused by the changed behavior of the reincarnated Sasuke. Maybe the reincarnated Sasuke is more open and friendly towards her than the original Sasuke, which would lead to different interactions between them.
If it's a crossover with the Fairy Tail guild, Natsu would be an interesting character to pair with Sasuke. Natsu is hot - headed and Sasuke is brooding. Their personalities contrast but they are both extremely powerful. Sasuke's Rinnegan powers could be used in combination with Natsu's fire - based magic in battles against powerful enemies. And they could have some great banter as they try to understand each other's worlds.