Answer:
I do think it is an example of realism.
Step-by-step explanation:
An Occurrence at Owl Creek Bridge is a short story written by American author Ambrose Bierce and it tells the story of Peyton Farquhar, who is being prepared for his execution by hanging, during the American Civil War.
As asked in the question, the speaker uses romantic techniques with different purposes, such as setting and to criticize external situations to the character like the war itself. Even though these techniques the story occurs during American Civil War, which is a real context, so the armies were. It also mentions some of the measures taken by the different troops, such as Farquhar's death by hanging and why he was in that situation: he undertook a mission to prevent Union's Army from crossing the bridge. It is also relevant to look at the title of the story, where the word occurrence appears, meaning that it is something that usually happened or that was very common, a part of daily life during war.