The common perception of a medieval executioner is a man in a black mask with a big axe. But why bother trying to maintain anonymity? Surely in a medieval society it would be next to impossible to do so?
Medieval towns and cities were (relatively speaking) small communities and prominent citizens would be well known to most inhabitants. If everyone knew who the tanner or the baker or the farrier was it seems unlikely that people wouldn’t also know exactly who the town executioner was.
Mask or no mask, if your friend Henry is paid by the local lord, works daily in the jail, is often seen sharpening a big axe and is mysteriously absent every time there’s a public execution; it surely wouldn’t take long to figure out he was the one carrying out the execution.
Greetings. While you're waiting, you might be interested in this answer about French executioners by /u/OakHeartIX:
Hope this helps.