England meet Sweden in Samara as favourites to reach their first World Cup semi-final since 1990 but Krafth says they must be wary of Young's diving.
He said: "I am a Manchester United supporter and I have seen Young a lot — a good player who is very fast.
"He likes to cut inside and shoot. In the box, we will have to look for his diving. Not do anything stupid."
Bologna defender Krafth also thinks winning their last-16 tie against Switzerland in regulation time will help Sweden. England needed penalties to see off Colombia.
"It's an advantage for us that their game went to a penalty shootout," he said. "We know which players will take penalties and where they'll shoot.
"They also had to play 30 minutes more than us."