A great plot could involve Ratchet being pregnant during a time of war or great danger for the Transformers. His pregnancy could become a symbol of hope for the future. The other Transformers would have to protect him while he is in this vulnerable state. And Ratchet himself could be exploring newfound emotions and relationships because of the pregnancy. For example, he might form a closer bond with a particular Transformer who is very protective of him. There could also be a mystery surrounding how he became pregnant in the first place, which could add an element of intrigue to the story.
Perhaps the plot could center around Ratchet's pregnancy being the result of some sort of scientific experiment gone wrong. He might be initially afraid and ashamed of his condition. But as the story progresses, he realizes that this new life inside him could be a chance for a new beginning for the Transformers. The other characters could have mixed reactions. Some might be supportive, while others might be skeptical or even hostile. This would create a lot of drama and character development opportunities. The story could also explore how the Autobots and Decepticons might react differently to Ratchet's pregnancy, adding a layer of complexity to the Transformers' universe.