The formation 2-6-2 isn't used very much, because training is lost. It is a risky tactic where a manager wants to boost the midfield rating. When playing 2-6-2 experienced players are needed to prevent confusion.
Normally only national teams, who don't suffer the training loss, will use this tactic. But teams that have a very important match, and are willing to lose training for a good result, are also known to use this formation too.
This is an example of 2-6-2 where is tried to dominate the midfield and also boost the attack ratings as much as possible. The defense will be very poor but a better midfield reduces the number of chances that the opponent will get. And with nice attack ratings the team will possibly score a lot of goals.
In this formation the sole goal is to boost the midfield as much as possible, in order to receive as much chances as possible and prevent the opponent to get any chances. All 4 inner midfielders, the two wingers AND the two offensive central defenders are selected on their playmaking and stamina, thus the midfield rating will be maximised. The forwards will get a lot of chances and they will have to knock som in because, the defence is actually formed by just a goalkeeper, so if the opponent has a chance it will probably go in.