I just noticed The Order of Ancient members carrying Yggdrasil symbol with them, like Templars Shay Patrick Cormac and Juhani Otso Berg. I wonder if there is deeper meaning or connection. :
Shay Patrick Cormac: A new Mythology for Assassin's Creed?
Shay Cormac Meets Arno Dorian and Kills his Father - Assassin's Creed Rogue Remastered - YouTube