Similarities
Both are about soldiers in wartime.
Both present a first-person narrative.
Both provide graphic images of death and war.
Differences
Remains has a faster paced rhythm, Exposure has a more measured pace, reflecting the way the soldiers are waiting.
Remains is about modern warfare, Exposure is about World War One.
Remains has a structure which disintegrates towards the end, Exposure uses a more regular structure.
Exposure is written in the present tense about an experience that is unfolding. Remains is also written mostly in the present tense, but is about a past experience, showing the lasting trauma of the experience of war for this soldier.