I don't see why Sound Wave would have any advantage, even efficiency, over a similar Zen 5/6 design. Microsoft must really want ARM if they're having this chip made.
They did countless attempts to use ARM but all failed. Consumers didn't care because they couldn't run their software. Microsoft won't solve the problem until they will provide a way to run all relevant software on ARM.
A year or two ago I used a Windows 11 laptop with an ARM CPU, and at least for me everything just worked. The drivers weren't as good, but all my x86-64 software ran just fine