As Hiro and Violet are from different series, they have never met in canon. Even though a few Disney crossover video games could have them cross paths with each other or get them added in the same team, by the player's choice.
Both Hiro and Violet are young superheroes that have their own groups. Just as Hiro and his friends have armor and gear that works with their expert fields, Violet's super-suit was designed to work with her powers by turning itself invisible with her. Outside of their hero lives, they attend school/college like most kids their age. While their own superheroes adventures have helped them to build up a lot of confidences in themselves, since they were originally very shy people with little friends until they came across and befriend people that were similar to them.
Violet's superhero team is made out of her family, while Hiro's team on the other hand is made out of his friends and an upgraded Baymax. The two can stand up for each other whenever problems occur in their ways when they face obstacles/villains that come their way, such as when either Hiro or Violet faces danger, both are determined to protect others from whatever harm comes their way. In Violet's superhero world, Supers were made illegal before she was born, until she, her family and a few other Supers changed the law to make them legal again. While the second part of season two in Big Hero 6: The Series, has Hiro and his friends coming across a police chief that dislikes superheroes and views them as vigilantes, and after an incident of them trying to help a friend who wasn't in control of his own body, the one minded chief made it his mission to find and arrest Big Hero 6.
In the Lego video game of The Incredibles, Violet is shown to know her way around computers, just as Hiro knows his way around both computers and robotics. Along with them having obsession skills that have allowed them to notice the odd behaviour of others and piecing things together in order to form parts of the big picture, before they take action.
Hiret is one of the main het ships of the Modern/Futuristic Four crossover Disney fandom, where the two are two of the four main members, along with Wilbur from Meet the Robinsons and Penny from Bolt. It is often shipped alongside Wilpenny, as well as it commonly being rivaled with Willet. The ship is also one of the main ships of the other known Big Hero 6/The Incredibles crossover fandom, Big Incredible Heroes.
Fans of the ship will usually move the events of The Incredibles to the present timeline events of Big Hero 6 so Violet and her family can team up/cooperate with Hiro's team. Some shippers will have Hiro and Violet interact with each other due to both being the same age. Typically they will bond over their superhero lives, and relate to each other. Other fans, however, prefer to have Violet and Hiro as siblings or just friends. There have even been times where Violet is given BH6 style armour, that Hiro made for her. In some AUs, the two are sometimes portrayed as Ladybug and Cat Noir from Miraculous Ladybug.
On AO3, the ship only has 6 fanfics, while Fanfition.net has only 4. Even though the ship's fanbase is quite on those two fanfiction websites, it does have a reasonable size fanbase on both Deviantart and Tumblr.
- They are two of the playable characters in Disney crossover games, like Disney INFINITY, Disney Emoji Blitz, Disney Magic Kingdoms and Disney Heroes: Battle Mode.
- Violet is the oldest sibling in her family, while Hiro is the youngest.
- Both of their films were released in November.