Nikon is working on the holy grail of mirrorless system camera sensor tech. In the newly published patent application (submitted in January 2018) they present a new sensor:
In order to realize a global shutter in a CMOS image sensor, there is known an imaging apparatus in which a storage section is provided to a pixel.
Moreover the sensor has on sensor phase detection pixels similar to Canon’s dual pixel tech.If Nikon can really translate this into their new FF mirrorless it would certainly mark a quantum leap over current Sony’s.