Sordsman is a Mii from the Switch.
Sordsman is an unused Mii, whose Mii data file can be found in Super Smash Bros. Ultimate. He isn't used by the game, nor appears anywhere else. His Mii data file filename is mii_sordsman.bin, which is similar to the Swordfighter's Mii data file filename, but Sordsman's doesn't have a "w".
His Mii name in his Mii data file is けんじゅつE, which can translated to "Kenjutsu E", kenjutsu being the art of sword fighting. The name Kenjutsu could also be a reference to the fact that Ken- is a common name starter for males in Japan. While the "E" part is currently unknown, this means Sordsman's name is Kenjutsu. Despite this, the name on the Mii Library is still his Mii data file filename ("Sordsman") as the used Mii Swordfighter has the same name, and the name "Sordsman" is distinct enough to warrant calling him that.
His Mii ID is as follows: FD 94 1B 9B 96 7A 4E 42 9D 1F 73 88 FE 02 89 CC
Sordsman is one of many Miis to not have a proper name. His Mii name in his Mii data file is more of a title than a name. Due to this, I have gone with the name "Sordsman", derived from his Mii data file filename.
Sordsman looks very similar to Swordfighter in appearance. Their Mii data files only contain two differences, actually: the first is his Mii ID (above) and the second is most obvious: Swordfighter's favorite color is royal blue, while Sordsman's favorite color is red.
Out of the four Miis in his game, Sordsman is the only unused Mii.
Sordsman is an unused Mii, and while some unused Miis have appeared in promo art before, Sordsman unfortunately does not.