The Chaos Marines are effectively the same as loyalist Tactical Marines, but like most of your infantry, they have the Champion of Chaos trait. This is shorthand for any unit that has one of the following Faction keywords:, BLACK LEGION, WORD BEARERS, IRON WARRIORS, ALPHA LEGION, NIGHT LORDS, WORLD EATERS, EMPEROR’S CHILDREN, FALLEN or RED CORSAIRS. Make the Primaris Space Marines into regular Space Marines, and Make regular Space Marines Primaris size/bulk.