The Hikvision UK Download Portal will give you a basic breakdown of which models come under which firmware family, e.g. G3 platform(2XX6G2 2XX7G2 2XX6G0 XE6XXX) means the G3 Family covers all the non-(C) G2 AcuSense and ColorVu cameras like 2347G2 or 2686G2.
Also, at the bottom of the list of firmware families on the EU Portal, you will see a document called IPC Models of Different Platforms_191209.xlsx which breaks down all the firmware families with lists of the majority of camera models in each family.
On the camera web interface - systems settings page look for the "Firmware Version Property" value which will have in it something like G1 or H3 or whatever - that is the firmware platform you need.