I think it could be the blacksmith OC who has a strong moral code. For instance, an OC who refuses to make weapons for evil lords or sells his work only to those who he believes will use it for good. This type of character adds depth to the fanfiction and can be very appealing to readers who like complex and morally upright characters.
One plot idea could be an OC who is pregnant and trying to hide it from powerful enemies in King's Landing. She has to navigate the dangerous political intrigue while protecting her unborn child.
One idea could be an OC who is pregnant and is trying to hide it from the warring factions in King's Landing. She might be a servant in the Red Keep and is afraid of what will happen if her pregnancy is discovered, as she doesn't know who the father is among the many lords and knights who frequent the castle.
Her appearance should also fit the world. If she's pregnant, she would likely have a different wardrobe to accommodate her growing belly. She might wear loose - fitting gowns or robes that are typical of the 'Game of Thrones' setting. And don't forget about her skills and abilities. If she's good at horse - riding, she'll have to adjust to that during pregnancy. All these details combined will make her a believable character in the fanfiction.
OC Myranda in fanfiction could be used to explore different relationships. For example, she could have an unexpected friendship with a character that was her enemy in the show. This could lead to some really cool plot twists. Also, the author could change her role in the political intrigue of Westeros. Instead of being just a tool for Ramsay Bolton, she could become a key player in her own right, manipulating the power dynamics in a different way.
The OC Greenseer could act as a guide. They might use their visions to lead characters to hidden treasures or safe havens. For instance, they could show a group of refugees the way to a secret valley where they can survive the winter and the war.
An OC Stark might be more politically astute than the original characters. They could form different alliances, like making a deal with the Iron Bank that gives the North more financial power and influence. This would shift the power dynamics not only in the North but also across Westeros. The original plot of various houses vying for the Iron Throne would be affected as the North becomes a stronger and more independent force.
There are many fanfiction communities where you can look for such stories. For example, FanFiction.net could also have 'Game of Thrones' fanfics with an OC being pregnant. Try to use the search function on the site and narrow down the results by adding relevant keywords like the character traits you prefer for the OC or the specific plot elements you want in the story.
There are some that explore the relationships around her during this time. Her advisors might have different opinions on how to protect her and the unborn child. And her dragons could also play interesting roles, like being extra protective of her in a more sentient way than in the original series.
Yes, there are quite a few out there. Some focus on how Cersei's pregnancy would change her power dynamics in King's Landing. For example, in some fanfictions, her pregnancy makes her more vulnerable to political attacks as her enemies see an opportunity to undermine her while she is in a physically weaker state due to pregnancy. However, the quality of these fanfictions can vary greatly.