A cool plot could be that the Ancients from Stargate have some sort of connection to an ancient race in the Farscape universe. The Stargate characters could be on a quest to discover this connection and in the process, they team up with the Farscape gang. They might find that there are similarities in the technology or the way the two races ascended, which could lead to new knowledge and power for both groups.
Maybe a character from Stargate, say Daniel Jackson, gets stranded in the Farscape universe. He could use his knowledge of ancient cultures and languages to help the Farscape crew with some of their own mysteries. And in return, the Farscape crew could teach him about their unique technology and ways of survival in a very different and often hostile galaxy.
In farscape stargate crossover fanfiction, a fascinating idea is the combination of the different methods of space travel. Farscape has its own style of starship travel and Stargate has the wormhole - based travel. Writers could create stories where characters have to figure out how to use both methods to reach a common goal. Additionally, the clash of different leadership styles from the two shows' characters can add drama. Some characters are more authoritarian while others are more democratic, and seeing how they interact in a crossover situation can be very interesting.
One idea could be that the Stargate team discovers a world where the Sentinel abilities are a natural part of the population. The Sentinels' powers could be used to help the Stargate team in their exploration and battles against alien threats. For example, their enhanced senses could detect hidden Goa'uld symbiotes or hidden traps in ancient ruins.
One idea could be to cross Stargate Universe with Stargate SG - 1. Maybe the Destiny crew discovers an ancient technology that was originally developed by the SG - 1 team on Earth. This could lead to a joint mission where both crews have to work together to unlock the secrets of the technology and use it to save both their ships and Earth from a new threat.
One idea could be a Highlander character finding a Stargate and being transported to different planets. They could use their immortality to survive in the various dangerous situations on alien worlds and perhaps encounter Goa'uld who are interested in their immortality.
Maybe there's a race in the Stargate universe that has developed a technology similar to the Borg in Star Trek. The Starfleet and Stargate teams come together to study this new threat. They could exchange knowledge about artificial intelligence and combat strategies. For example, the Stargate team might introduce the concept of Ancient technology, which could be used to counter the Borg - like threat in ways that Starfleet has never considered.
A possible plot could involve an immortal villain from the Highlander world using the Stargate network to spread chaos across different planets. The SG1 team, with the help of some friendly Highlander characters, has to track him down and stop him before he causes too much destruction.
John Crichton from Farscape and Jack O'Neill from Stargate. They both have a sense of humor and are great leaders. Jack's military experience combined with Crichton's scientific knowledge would make for an interesting dynamic. They could exchange stories about their different universes and come up with some wild strategies to deal with any threats.
Well, in Roswell Stargate crossover fanfiction, there might be a plot where the characters from Roswell get involved in Stargate missions. Imagine the Roswell gang having to deal with the Goa'uld or the Replicators. It could also be about how the technology from Stargate affects the lives of the Roswell aliens. For instance, the Stargate could be a way for them to find a cure for their alien - related problems or a means to enhance their powers.
One idea could be that the Spartans from Halo are sent through a Stargate to an unknown planet in the Stargate universe. They have to team up with the SG teams to fight off a common enemy like the Flood that has somehow spread to that planet. Another could be a scenario where the technology from both universes is combined. For example, the Covenant's energy shields are integrated with the Stargate's shield technology.
In a Stargate Babylon 5 crossover fanfiction, a possible plot could revolve around a mysterious energy source. This energy source could be something that is of great interest to both universes. Scientists from Stargate and Babylon 5 could team up to study it. However, different factions within each universe may have different ideas about how to use this energy. This could lead to internal conflicts as well as conflicts between the two universes. It would be a story full of political intrigue, scientific discovery, and adventure.