𝖶𝗋𝗂𝗍𝗂𝗇𝗀 𝖳𝗂𝗉𝗌 𝖿𝗈𝗋 𝖫𝗈𝗌𝖾𝗋𝗌

𝖥𝖺𝗇𝗍𝖺𝗌𝗍𝗂𝖼 𝖡𝖾𝖺𝗌𝗍𝗌 𝖠𝗇𝖽 𝖧𝗈𝗐 𝖳𝗈 𝖶𝗋𝗂𝗍𝖾 𝖳𝗁𝖾𝗆 (𝖵𝖨𝖨)

✎ 𝖧𝗂𝗏𝖾 𝖬𝗂𝗇𝖽𝗌

Okay, so I had to look up the Stepford Cuckoos/Five-In-One (because I'm a loser and I'm not into superheroes), and I apologize if anything I say contradicts the Stepford Cuckoos' abilities/powers. I'm not sure how to write for them specifically, but I do have some tips on writing a hive mind in general.

✎ 𝗞𝗻𝗼𝘄 𝘁𝗵𝗲 𝗱𝗲𝗳𝗶𝗻𝗶𝘁𝗶𝗼𝗻 𝗼𝗳 𝗮 𝗵𝗶𝘃𝗲 𝗺𝗶𝗻𝗱
Also know that there are different kinds of hive minds (Examples taken from Wikipedia)
✎ Collective consciousness or collective intelligence, concepts in sociology and philosophy
✎ Groupthink, in which the desire for harmony or conformity in the group results in an irrational or dysfunctional decision-making outcome
✎ The apparent consciousness of colonies of social insects such as ants, bees, and termites
✎ Swarm intelligence, the collective behavior of decentralized, self-organized systems, natural or artificial
✎ Universal mind, a type of universal higher consciousness or source of being in some esoteric beliefs
✎ Group mind (science fiction), a type of collective consciousness
✎ Egregore, a phenomenon in occultism which has been described as group mind

The kind we think about most is probably collective consciousness and the hive mind that is associated with insects.
So basically it means that everybody is connected to everybody. There are no secrets. There is no individuality. Just one huge ball of shared information that is constantly being added to the more the individuals included within the hive mind experience different situations.
In the writing world, however, there are no set parameters. You can take this information and go wherever you want with it. You're a writer, after all, and that's what you do! You aren't obligated to follow the exact definition.

✎ 𝗦𝘁𝘂𝗱𝘆 𝗮𝗻𝗶𝗺𝗮𝗹𝘀 𝘄𝗶𝘁𝗵 𝗵𝗶𝘃𝗲 𝗺𝗶𝗻𝗱𝘀
You don't actually have to go outside and study them; I mean research their behaviors as well as drawbacks that they sometimes experience.For example, ants are followers. They leave scent trails so that other ants know where they have been, and many ants follow the ones in front of them without any way to control themselves; they simply can't help but follow the ants in front of them. (This explains why you always see groups of ants moving in single file lines)

"Most ants navigate by using eyesight,
but some army ants are completely blind – and it's possible for them to become disorientated and march in circles until they die of exhaustion. It's known as an 'ant mill' and is one of the strangest sights in nature. Army ants navigate by following pheromone trails left behind by others. However, should enough of them lose the scent they begin to follow the ant immediately in front and a huge ant spiral forms."

Basically, the ant in the front of the line turns, and sometimes the line is so long that the ant in the front collides with other ants in the line. Naturally, the ant begins to follow. The ants are now caught in a vicious circle where everyone is following the person in front of them. And, as the article states, they eventually die of exhaustion.
This is only one of the drawbacks, and this only pertains to ants.
This whole section basically is saying DO YOUR RESEARCH!!

✎ 𝗞𝗻𝗼𝘄 𝗰𝗼𝗺𝗺𝗼𝗻 𝘁𝗿𝗼𝗽𝗲𝘀 𝗮𝗻𝗱 𝗰𝗵𝗼𝗼𝘀𝗲 𝘁𝗵𝗲 𝗼𝗻𝗲𝘀 𝘆𝗼𝘂 𝘄𝗮𝗻𝘁 𝘁𝗼 𝗰𝗵𝗼𝗼𝘀𝗲 𝗮𝗻𝗱 𝗮𝘃𝗼𝗶𝗱
Common tropes associated with a hive mind/creatures who are a part of a hive mind:
✎ Individuals are never found alone, always in groups
✎ Individuals talk at the same time, in the same monotone voice
✎ Individuals walk in time with each other
✎ The hive mind is always controlled by a single ruler, usually a Queen
✎ Individuals work together incredibly well and are nearly unstoppable

These tropes aren't at all overused or stupid; there are simply too little well-known stories containing hive minds for it to become too cliche.
My advice is to use these tropes however you'd like, but still add your own little twist on it.
After all, the twists are what make your story unique!