In this fanfic, the pregnancy could bring out new sides of their personalities. Steve might show a softer, more nurturing side that he's never shown before. Kono could become more reflective about her own upbringing and how she wants to raise her child. There could also be some conflict, like whether Kono will take a long maternity leave or try to come back to work quickly. This would create drama and further develop their relationship.
There could be a fanfiction where Kono and Steve find out about the pregnancy in a very dramatic way. Maybe during a dangerous mission, Kono starts to feel unwell and later discovers she's pregnant. This could add a whole new layer of tension and emotion to their relationship.
A possible plot could be that Kono and Steve are trying to keep the pregnancy a secret from the bad guys they are investigating. They fear that the criminals might use Kono's pregnancy as a way to get to them. So they have to be extra careful in their daily lives and on missions.
There could be a fanfic where Steve and Kono's relationship takes a new turn with a pregnancy. It might explore how they deal with the unexpected news. Maybe Steve is initially shocked but then becomes super protective, while Kono is determined to continue her work while also preparing for motherhood.
In such a fanfiction, there could be a lot of drama. For example, Steve might be overly protective of Kono during her pregnancy. And Kono could struggle with balancing her duties and her pregnancy. Also, their friends in the team would surely have different reactions and support them in various ways.
They might have a very adventurous married life. Since they are both part of Hawaii Five - 0, they could continue to solve crimes together while also dealing with the normal ups and downs of a relationship. For example, Steve's often - impulsive nature might sometimes clash with Kono's more level - headed approach, but they would work through it because of their deep love and respect for each other.
One great fanfic idea could be Steve going on a solo mission to rescue a kidnapped scientist. He uses his combat skills and sharp intellect to track down the bad guys. It could involve intense fight scenes and some clever detective work.
She might be in a coma for a while, which would make her teammates worry a great deal. They would visit her in the hospital constantly, hoping for her to wake up soon.
Steve could be framed for a crime he didn't commit. He then has to clear his name while being hunted by the very people he once worked with. It would be a thrilling plot with lots of twists and turns.
The wedding would be a big celebration with all their Five - 0 team members present. There would be lots of music and dancing. Hawaiian music would fill the air, and everyone would join in the hula. The food would be a mix of local Hawaiian delicacies and some of Steve and Kono's favorite dishes from their travels.
I'm not aware of any particularly popular ones. Fanfiction can be quite niche and vary widely in popularity. There may be some out there, but it might take some searching through various fanfiction websites to find.