This is the second time that Sunset Overdrive has been rated for PC, with the Korea's Game Rating and Administration Committee listing the game back in May. The ESRB rating doesn't cough up any new info, although it seems pretty clear at this point that a PC port is definitely on the horizon.
Sunset Overdrive was released on the Xbox One back in 2014, and was one of the first major exclusives for Microsoft's console in its initial launch year. You can read our review here.
Obviously there's no official confirmation by Microsoft at this point, although typically the ESRB has been on point when it comes to rating games ahead of a formal reveal.