This chart summarizes the DACs used in Genos, SX900 and EW410:
Genos MAIN AK4490EQ 32-bit
Genos SUB1, SUB2 AK4396 24-bit
Genos SUB3, SUB4 AK4396 24-bit
SX900 MAIN, PHONES AK4396VF-E2 24-bit
SX900 SUB1, SUB2 AK4396VF-E2 24-bit
EW410 PHONES AK4430 24-bit
EW410 D-AMP YDA176 24-bit
YDA176 is a digital amplifier and has its DAC built-in. This is one way to save cost in the E-series design. The YDA176 drives the speakers.
The part numbers with "AK" are designed and manufactured by Asahi Kasei Microsystems (AKM). AKM is one of the Japanese companies that suffered a fire during the pandemic. Yamaha relies heavily on AKM. Shortage of parts from AKM is one of the major reasons that Yamaha keyboard products have been delayed.
These parts don't just perform digital-to-analog conversion, especially higher-end components. They often incorporate digital filtering and other specific hardware functions -- all configured by software. So, even if you could swap out a part for another one, there's no guarantee that they will be software compatible and configure in the same way!
DACs are usually followed by one or two stages of analog filtering and amplification. The analog circuits are tuned for the specific characteristics of the DAC component.
If you want a better (different) DAC with Genos, use its DIGITAL OUT. The bit stream comes directly from the tone generators. I doubt if it will make that much difference in a mix.
Don't worry about DACs. Worry about peace and hunger. :-)
All the best -- pj