They Belong in a Museum

Needs Royal Court. Sponsor a courtier or guest with the Adventurer inspiration, wait for them to complete the adventure and come home, then appoint that same character as your Antiquarian from the court positions screen. The one way to fumble it: letting the adventurer wander off after their return - keep them at court until the appointment is made. Do it with the same adventurer you're using for One of a Kind and the whole thing is one workflow.