I know, he is a rapper, but I also heard that there is some influence of trap in his music (there is a song called 'trap queen'). What kind of genre is he? Is there an official genre for this mix of rap and trap?
From this article http://masetv.com/fetty-wap-names-gucci-mane-as-influence-behind-his-ignorant-rb-music/ he refers to his music as "ignorant R&B"
The Awards and nominations chart below on wikipedia https://en.wikipedia.org/wiki/Fetty_Wap#cite_note-42 shows that he received nominations for mainly HipHop and Rap, but this doesn't mean his music can't also include other sub-genre influences(i.e. trap). Personally, being a regular listener of his music, I consider him mainly trap.