https://www.gamespot.com/articles/e3-2018-assassins-creed-odyssey-modern-day-story-p/1100-6459452/

Assassin's Creed Odyssey will pick up its modern day story with a familiar face. As revealed at E3 2018, Layla Hassan's story hasn't come to an end just yet, and will continue in the forthcoming iteration. If you haven't wrapped up Assassin's Creed Origins just yet, we recommend to stop reading now as spoilers will follow.

While we don't know much about where the modern day story will go, or Layla's connection to Alexios or Kassandra, the last time we saw her, she was heading to Alexandria with William Miles. Faced with few other options and her partner from the Sigma Team captured, she allies with Miles and the Brotherhood, though she is not a member herself.