The measurement of the time-dependent CP violation parameters for $B$-meson decays is crucial for tightening the constraints on the unitarity triangle and for the search of new physics beyond the Standard Model. A clean environment for the study of $B$ decay channels is provided by $B$-factories. With a design luminosity of $8\cdot 10^{35} \; cm^{-2}\; s^{-1}$, leading ultimately to an integrated luminosity beyond 50 ab$^{-1}$, the new $B$-factory SuperKEKB will exceed the record instantaneous luminosity of its predecessor KEKB by a factor of 40. The new Belle II detector will exploit the expected high statistics data sample thanks to a major upgrade of the tracking system, including a novel pixel vertex detector in its innermost part. Additionally, the detector capabilities will be complemented by substantial improvements in the reconstruction software. A strategy for CP violation analysis is being developed in order to maximally exploit the new data set and to characterize the sensitivity of Belle II for various benchmark $B$ decay channels.