Perhaps the most interesting concept in Watch Dogs Legion is that every single character in its world is playable - including a descendant of Assassin's Creed's Jacob Frye.
For those unacquainted with Jacob Frye, he was one of the two protagonists of Assassin's Creed Syndicate, alongside his older twin, Evie. A Master Assassin of the British Brotherhood, Jacob was active during the Victorian era in London.
Watch Dogs Legion transpires almost two centuries after Syndicate, but also takes place in London - that's why it makes sense for the game to indulge one of Ubisoft's other biggest series, introducing an innocuous but nonetheless present joint world.
Here's a tweet showing off Jacob and Evie Frye's descendant, who works as a professional hitman in post-Brexit London.https://twitter.com/ANerdWonder/status/1282568670342832128?s=09
"Watch Dogs Legion will let you play as a descendant of Jacob Frye," reads the tweet. "Pretty neat connection between both franchises."
As you can see, the character in question is named Sandra Cassidy. She's a professional hitman who legs it around with a Desert Eagle - hopefully one with slightly less kickback than the one in COD 4.
Anyway, the logic backing this up is that Cassidy showed up after someone previewing the game emphatically plugged in some names from Assassin's Creed.
You can see under her profession that the player specifically searched for "Jacob Frye descendants" - whether or not there are other people descended from your favourite assassins isn't known at present, but the Frye twins probably make the most sense as ancestors due to their London-based activity.
There's also another cool Assassin's Creed Easter egg in Watch Dogs Legion, meaning that the devs might have included several subtle nods to the series.