One player scores nearly every goal – do you change anything?

I would give him a challenge, but I would keep it connected to the game. I would not say “you cannot score” or make him complete three passes first. That punishes the thing he is good at and creates fake decisions. Instead, I might speak to him between games: “When two players come to stop you, can you spot who they leave free?” Or, “Can you win it back quickly when you lose it?” That gives him something harder to notice without stopping him attacking the goal. I would also change the groups so the other players get games where they cannot simply wait for him to solve everything. The best challenge is usually a harder football problem, not a handicap.