I was looking at items in the shop to purchase with in game currency and found that several items have a prestige logo over the top. What is prestige in this game? Is this after completing the main story or is there a prestige system in online multiplayer?
From this reddit post, we can say, that there is no prestige system itself. The items are just "prestigious".
Buying them gives you the item itself plus a unique skin for it, skipping any progression required to unlock them.