A goal every 136 minutes in the Prem.
That puts Trossard at equal ninth in the league for efficiency (with Richarlison), according to FBRef if you rule out players with fewer than 10 90s.
List of the guys more efficient: Isak, Palmer, Haaland, Jota, Wood, Salah, Adebayo, Olise.
Being a sub skews that stat up for him, but he's a hell of a marksman.