Those ES9000 series DAC ICs have 8 channels so two pieces are needed to cover 8 channels. Some (not all) of the so called 7.2 models may have only 1 ES9006 because the .2 (subwoofer channel) is actually two sharing the same signal.
For models that have a total of 9 channels including the subwoofer channel will therefore need two such DAC ICs, whether they are the ES9006, 9007. The top Yamaha models such as the 8A will have two 9026 Pro whereas the former flagship A3080, while also have two, but only the ES9026 Pro is used for the main channels, and the lower grade ES9006 or 9007 is used for the surround/height channels.
The PCM5100 series (5100,5101, 5102) are "stereo" DAC ICs that have only two channels so they are typically used for zone 2 and zone 3.
I don't know your source of information about the A2A's PCM5102A, if that is true then it will have at least 4 of those to cover 8 channels (including the subwoofer channel), and would need one more if it has zone 2.