Suss is a Mii from the Switch.
Suss originally appeared as the default Mii for Neksdor town's Shady Merchant Father role in the files of Miitopia (Switch, Demo), but unused within the demo itself. He later appeared in the full game of Miitopia (Switch). Once the player replaces him with a Mii of their choice, Suss 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 Town01_MerchantParent.charinfo.
His Mii name in his Mii data file is あやしいおや, which translates to "suspicious". His height is set to 115 and his build is set to 47. His Mii ID is as follows: FA DD 70 BF 51 2A 4B 55 93 7E B7 C6 3B 33 39 1E
His Mii data file does not contain any unused Mii data.
Suss' role in Miitopia (the Shady Merchant Father) is described as so:
Rakes in the money by feigning illness.
Amazed at his daughter's schemes.
He seems to bear resemblance to a Mii featured in Miitopia (3DS) promo art, as it seems a handful of the Miitopia Switch default Miis were based around Miis that appeared in promo art for the original game, but it's unconfirmed if Suss and the promo art Mii are meant to be the same character.
The names of the default Miis in Miitopia Switch often vary drastically depending on region. Suss' name on the Mii Library is going off of the US English version, for consistency. A chart containing all of Suss' names is located at the bottom of this page.
Suss unfortunately does not appear in any promo art. Below is a screenshot of him in-game as his role in Miitopia.
While Suss himself does not appear in any official promo art, a very similar Mii does appear in promo art for Miitopia (3DS), where they're given the Thief job.
This Mii originally appeared on the Switch!
Here's how to recreate them on the Switch:
Names in other languages
US English: Suss (pun on the word "sus", or "suspicious")
US French: Arnac (pun on the French word "arnaque", meaning "scam")
US Spanish: Maro Chant (pun on the word "merchant")
EU English: Junkle (pun on the words "junk" and "uncle")
EU Dutch: Kramer
EU French: Arnac
EU German: Skonto
EU Italian: Tarocco
EU Spanish: Pol Morro
JP Japanese: ウサン (Translates to "Usan")
KR Korean: Suss
CN Chinese: Suss
TW Chinese: Suss
Source: Miitopia (Switch, Demo)
Mii Studio code
Unfortunately, as the Switch no longer supports QR codes, the only way to obtain this Mii yourself directly is via importing them into your Mii Studio with this tool.
This is Suss' Mii Studio code:
You can download Suss' charinfo-format Mii data file here.