24.5MP FX-Format BSI CMOS Sensor
Dual EXPEED 6 Image Processors
UHD 4K30 Video; N-Log & 10-Bit HDMI Out
14 fps Cont. Shooting, ISO 100-51200
273-Point Phase-Detect AF System
3.6m-Dot OLED Electronic Viewfinder
3.2" 2.1m-Dot Tilting Touchscreen LCD
5-Axis In-Body Vibration Reduction
Dual Memory Card Slots
There are a number of small refreshes which help to address some of the problems or issues with the original Z6, which when added together make for quite an interesting proposition - especially if those problems particularly bothered you with the first iteration.
At the heart of the Z6 II is exactly the same 24.5 megapixel back-illuminated CMOS sensor as found in its predecessor, but it now comes with promised improvements to autofocusing, buffer, video and now includes a secondary card (SD) slot.
Some of those improvements come courtesy of the added Expeed 6 processor - meaning that the Z6 II (and Z7 II) now has two processors, instead of one.