Dudley is a Mii from the Switch.
Dudley originally appeared as the default Mii for the Greenhorne town's Dubious Mayor role in Miitopia (Switch, Demo). He later appeared in the full game of Miitopia (Switch). Once the player replaces him with a Mii of their choice, Dudley would never appear again, unless that Mii is deleted. His Mii data file can be found in \cmn\storedata\npc_default_mii.sarc and is named Town00_Mayor.charinfo.
His Mii name in his Mii data file is ちょうちょうk, which translates to "town mayor k". His height is set to 47 and his build is set to 127 (maximum). His Mii ID is as follows: 09 ED 79 54 28 AD 4A E5 94 B0 D0 0E FF F4 8A 38
His Mii data file does not contain any unused Mii data.
Dudley's role in Miitopia (the Dubious Mayor) is described as so:
The names of the default Miis in Miitopia Switch often vary drastically depending on region. Dudley's name on the Mii Library is going off of the US English version, for consistency. A chart containing all of Dudley's names is located at the bottom of this page.
Dudley unfortunately does not appear in any promo art. Below is a screenshot of him in-game as his role in Miitopia.
This Mii originally appeared on the Switch!
Here's how to recreate them on the Switch:
Names in other languages
Source: Miitopia (Switch, Demo)