The following phrases sound OK to me:
The reason this stands out is for its characteristics.
The reason this stands out is its characteristics.
However, "is for" feels somehow forced, and I can't find a guidance pointing at either form. I can't even properly categorize it (phrasal verb + to be + preposition is too generic for any search engine).
The second certainly seems more idiomatic, but neither sounds truly idiomatic, partly because both seem vacuous. What characteristics make it stand out? Except for the things dealt with by chemists and physicists, no two things have identical characteristics, but many things have some identical characteristics. For example, all living human beings have a head, a heart, a liver, etc. Moreover, we can distinguish among items by specific differences among common characteristics.
What is likely meant by the exemplified statements is probably something like:
What makes this stand out is its unique combination of these characteristics of x, y, and z.
