Kingdom selection is rather a crapshoot on Angelica. And without that being known, duchy selection is unknown. You are probably better off waiting until kingdom 4 or 5 is selected and then do some quick legwork to connect with some of the dukes. (I’m a committed count and I don’t even know where we will end up and have to accept not being sure of the tribe.)
That said, Scuttlebutt says Blackheart has its eye on Kingdom 5 with the Savannah To’resk.