From the Paladins: City of Crowns Kickstarter Page:
This deluxe Collector’s Box is designed to fit Paladins, City of Crowns, and all additional content, such as promos and metal coins. And yes, it fits sleeved cards. See the photos below. All boards sit together over the wooden components and smaller cards, keeping everything in its place. The box is the same size as the Collector’s Box for Raiders of the North Sea (295x295x69mm).
Collector’s Big Box to hold base game and expansion (29x29x69cm)
10 small cards (43x66mm):
8 Tavern cards (with yellow Vassals)
1 King’s Favor card (with yellow Vassal)
1 Reference card
8 Vassals (yellow wooden Workers)