These are fleets built by players. They will sometimes show up in other people's games, often being far stronger than the vanilla designs with their own styles and naming schemes. These factions will attack you on sight and will not hesitate to destroy your stations. Feel free to create one sensible page for each of your own factions in the game, but make sure to use this as a template:
Template Agent Edit
This faction is a template.
This faction's ships are completely blank, featureless squares.
This faction was created by a Wikia user as a template for an agent faction page.
Please note that the Lore section is completely optional.