“Thrawn Janet” (1881)
Robert Louis Stevenson (writer).
Read in 2017.
The phonetic Scottish is a notch better than most Romantic efforts in this vein, such as “Wandering Willie’s Tale” (1824), but it is still quite poorly planned, apparently disregarding how far removed from pronunciation normal English writing is. What I understand of the story is a crude moral fantasy.
References here: “The Dreams in the Witch House” (1933).