Playing a 3-4-3 with Tross, Ali J and Alexis as the front three wouldn't be the end of the world. Reasonable amount of goal threat there.More similar to him than Eden Hazard, Thorgon Hazard probably the most comparable. That napoli side quality though, with Insigne as well.
The point is Trossard might be a natural finisher but playing through the centre on his own probably not ideal. Jahanbaksh or even Alexis would make more sense.