To write an engaging scene, start with a lot of description. Describe how the gag looks on Connor, the material it's made of, and how it restricts his movement. For example, 'The rough fabric of the gag cut into Connor's synthetic skin as he struggled against it.' Then, show his emotions through his eyes or body language. Maybe he's frustrated or determined.
You could also build tension in the scene. Have the antagonists taunting Connor while he's gagged, or have a time limit for him to break free before something bad happens. Like, 'The deviant leaned in close, whispering threats as Connor's LED blinked red with anger, his muffled protests falling on deaf ears.' This creates a sense of urgency and makes the reader more engaged.
Another way is to focus on Connor's internal thoughts. Since he can't speak, his thoughts become more important. 'Connor's mind raced as he tried to find a way out of his predicament. The gag silenced his voice, but his thoughts were a cacophony of plans and strategies, his programming kicking into overdrive as he analyzed every possible escape route.'
One plot could be Connor being gagged by a deviant who doesn't want him to communicate with the police. This could lead to a situation where he has to find other ways to signal for help or solve the case at hand. For example, he might use his advanced visual sensors to send Morse code - like signals to his partner.
In a fanfiction, a child Connor could be created by an error in the CyberLife system. He might end up in the care of Hank, who is initially very confused but gradually grows to protect him. The story could explore how Connor, in this child form, experiences emotions for the first time. He might be fascinated by simple things like rain or the feel of a pet's fur, which are new sensations for him.
There's also 'Connor's Uncharted Territory'. In this fanfic, Connor gets involved in a complex case that forces him to make decisions that go against his initial programming. It's really interesting to see how he evolves in this story. The character development is well - written and keeps you hooked.