Use the full width of a 9v9 pitch. Play out of the crowded side, get a midfielder's head up in the middle, and switch it to a winger who has held his width, so he receives facing a block that is still travelling.
Work in a 3-2-3 across the full width of a 9v9 pitch. With the ball on one side, the far winger must hold his width and stay off the pitch's far line, not drift in to watch. Play inside to a central midfielder and switch it across. Coach the far winger to receive open and attack the space before the block slides. Rotate sides so both wingers learn to stay wide.
Width is created by players, not by cones, and in this exercise the hardest job belongs to whoever is furthest from the ball. The far winger has to hold his line on the opposite touchline while play develops without him, resisting the instinct every eleven-year-old has to drift towards the ball and get involved. He may be irrelevant for twenty seconds. Then he receives with a whole flank in front of him.
That instruction needs explaining rather than repeating, because from the outside it looks like a player doing nothing. A winger who tucks in has not just moved himself, he has moved the defender marking him, and the space the switch was going to arrive into closes before the pass is even considered.
Nine-a-side is where this first has to be understood, which is why it is worth spending a session on. The pitch is finally wide enough that a switch genuinely beats a defensive block, and the 3-2-3 gives you two players whose job is the touchline. It is the bridge to eleven-a-side and the habits formed here are the ones that arrive there.
Playing out of the crowded side rather than forcing through it is the enabling behaviour. Teams try to solve congestion with skill, which occasionally works and usually loses the ball in the worst area.
The midfielder in the middle is the hinge, and he needs his head up before the ball arrives. Receiving square means the switch is a second slower, and against a block that is already sliding, a second is the difference between a free winger and a marked one.
Save it to your private drills, then change the animation, adjust positions, swap equipment, or drop it into a session block. Or start from a blank pitch and build your own.