Isak’s leading the premier league in terms of goals scored per minute when you filter out all the guys that have played 5 minutes and scored.
The top 3 would be Isak, Haaland & Palmer.
That’s based on played around 2,000 minutes this season - Salah & Son would round out the top 5 although you have the likes of Wood, Trossard, Jota, Adebayo, Olise & Richarlison that have posted good ratios from Les game time.
Alternatively - filtering out PKs which anyone could take.
And adding Jota just as a FYI and because he's 12th in the PL Top goalscorers list (without penalties) :
Jota 1 goal per 115.00 mins (1,150 mins)
Haaland 1 goal per 128.53 mins (2,185 mins)
Isak 1 goal per 139.29 mins (1,950 mins)
Watkins 1 goal per 156.47 mins (2,973 mins)
Foden 1 goal per 157.69 mins (2,523 mins)
Palmer 1 goal per 167.46 mins (2,177 mins)
Bowen 1 goal per 177.50 mins (2,840 mins)
Son 1 goal per 178.43 mins (2,498 mins)
Nunez 1 goal per 181.45 mins (1,996 mins)
Salah 1 goal per 187.83 mins (2,254 mins)
Solanke 1 goal per 195.00 mins (3,120 mins)
Saka 1 goal per 251.36 mins (2,765 mins)