Available already:
– select all hosts to test
– windows updates>generate consolidated of update history. Select for example last 10 days and enable the filter including all WannaCry KB (one per line) for the OS you have. check in the footer the number of raw match the number of hosts to be sure everyone gave an answer.
you will have which KB was installed (matching the Os version), installation status, and reboot status if not yet done
Edit: a bit too late 🙂