Perhaps a new villain in town who is jealous of the attention Daphne and Fred get. This villain could try to disrupt their happy moment by spreading false rumors about the pregnancy or trying to harm Daphne's unborn baby.
Another option is a family member of either Daphne or Fred who doesn't approve of the relationship or the pregnancy. This person could cause a lot of internal conflict within the couple and the gang by trying to split them up or force them to make difficult decisions.
One idea could be that Daphne and Fred accidentally get pregnant after a wild adventure where they were stranded together for a while. They then have to face the reactions of their friends and family, like how Shaggy and Scooby might be shocked but also supportive in their own goofy way.
The Ink Demon could be an antagonist. He might see the pregnancy as a disruption to the order of the Bendy world and try to stop it. His dark and chaotic nature would be in contrast to the new life that's about to come.
The antagonists could be some members of their own clan who oppose the union or the pregnancy for various reasons, such as concerns about bloodline purity or political power within the clan. They might try to undermine Neji and Hinata's relationship and the pregnancy.
Perhaps a power - hungry Atlantean noble who doesn't want the child to be born because they fear the change it might bring. This noble could try to disrupt the pregnancy in secret, by spreading false rumors or causing problems in Atlantis that would put stress on Aquaman and Mera.
The Red Queen could be an antagonist. She might see the pregnancy as a threat to her rule or simply be jealous of the attention Alice is getting. She could try to cause trouble for Alice and Tarrant, like sending her minions to disrupt their peaceful life while waiting for the baby.
One possible antagonist could be a villain from their past who sees the pregnancy as a vulnerability. For example, a meta - human they previously defeated might come back to target them, thinking that with Caitlin pregnant, they'll be distracted and easier to take down.
Elena could be an antagonist. Since she has a history with Christian, she might try to interfere with Anastasia's pregnancy, perhaps out of jealousy or a desire to maintain some control over Christian.
Another possible antagonist could be Zelena. Jealous of Belle's happiness and the new life she's bringing into the world, Zelena could try to cause trouble. She might use her magic to create false scares or difficulties during the pregnancy, like making Belle believe there are problems with the baby when there really aren't.
The main antagonists could be the same organizations they have always fought against. For example, Umbrella Corporation or any other bio - terrorist groups. These groups might see Ada's pregnancy as a weakness and try to use it against them. They could target Ada to get to Leon or try to harm the unborn child to stop Leon from interfering with their evil plans.
It could be Gabriella's over - protective father. He might think that Troy isn't ready to be a father and tries to convince Gabriella to break up with him. He believes that their pregnancy will ruin Gabriella's future and he's very strict about it, causing a lot of tension between the couple and him.