Marrok, the most mysterious villain of Ahsoka, sported the lightsaber and armor of an Imperial Inquisitor but appeared well after the supposed disappearance of the organization. He was later revealed to have been resurrected by the Nightsisters and may have simply been the reanimated armor belonging to the eighth brother, an Inquisitor with a very similar helmet design to Marrok. Though Marrok was supposedly the last Inquisitor, the circumstances surrounding the end of the Inquisitorius are very vague, meaning others may be alive and wandering the galaxy long after the dissolution of the organization.
Source：https://www.cbr.com/what-happened-star-wars-inquisitors-before-original-trilogy/
