Martinelli keeps running towards the byline like a left footed winger which is fine if he was left footed, but he's not, so he can't cross or make passes from wide to in. As a right footer, he needs to be working angles to cut inside and move centrally to work the ball onto his right.
In contrast, Saka plays far closer towards the half space rather than the touchline which gives him ample opportunity to cut on to his left and shoot/cross.
If Martinelli is going to keep running wide, he's completely pointless to have on the pitch as he's doing the opposite of what you want from a right footer on the left.
