For now Kovacic is the only transfer made by Manchester City this summer. However they have been working on completing a way bigger deal for a long time. They are after Gvardiol as you know and their latest offer was really close to the amount Leipzig wanted for him. I still don't see any update on these negotiations but I assume Manchester City wouldn't stop until securing the deal.
Guardiola has been eager to see him in his team for a long time. This is going to be a really serious improvement in their defense and they will be even more challenging to be stopped. Maybe Gvardiol is a very young player for a defender but he is already impressive with his defending skills.