All game content is available in the game regardless of any past purchases - one of the changes of The Definitive Edition was the removal of microtransactions and the integration of such content in the unlock progression / quests completions and various other in-game mechanics.

You can open the ESC screen while in any world and check the built-in Reference, in case you want to know exactly how something it's supposed to be unlocked or obtained.

Owners / admins can also manage all unlocks from the player list - clicking on any player's name it's possible to alter the costumes, discoveries, crafts, perks and villager jobs.