As per subject header, you already know this could be done through Joinkeys. Why don't then read how to do it rather than asking? There are NUMEROUS examples on how to do it apart from the first option which is to read the Dfsort manual.
Terminology is critical in IT, where similar terms may mean very different things. And "joinkeys" does not exist in JCL -- period. It is a SORT construct, and SORT is NOT JCL (nor is JCL a SORT product).