Every player and every manager is eventually 'worked out' by opposition teams in the PL. It could take half a season or a couple of seasons. The solutions might not completely help, e.g. Pep keeps winning the league, but there is progression. That's what makes this league better than all the others. Certainly much better than Bundesliga.
Klopp's rock and roll football for example has been exposed enough after initial successes. Salah on his left foot has been sussed after being the current best striker in the PL (going by him holding the PL record).
Haaland has many strengths but also quite obvious weaknesses too.
If stopping City mainly means stopping Haaland (because Sterling and Jesus' pace is no longer the threat from KdB's through balls) then teams will start working this out soon enough. In the meantime, during this honeymoon period, Haaland looks like the virgin bride everyone wants to lay. Rightfully so.