I brought my key to Shipwrecked but i can't create my epic city island because i can't acces the crafting tab.
You should be able to craft these structures in Shipwrecked and ROG too, it would be awesome to be able to make a city in these worlds but as it stands right now spawning a slanty shanty and i imagine any other structure like it will crash the game, of course hamlet's still in beta and i hope that by bringing attention to this it will later become a feature.
Also one more thing, you can't craft any Hamlet Items in Shipwrecked apart from the shared ones as well as in ROG. I feel like you should be able to craft any item from any DLC as long as i have them enabled, this would make preparation to go in one of them easier, for example you could make a cloth sail in hamlet to go into shipwrecked. And you wouldn't have to travel to another world just to craft some items as well.
Take Key to the City to a Shipwrecked World.