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.
Microsoft already designed a modified ARM ABI [1] compatible with emulated X86-64 just for this transition. But it's a Windows 11 feature. I wonder if the refusal of many of us to switch from Windows 10 is part of the reason why they're still idling on an ARM strategy.
Part of the issue was incomplete amd64 emulation on windows which is why several MS products continued to ship 32bit - because while they might recompile their software for ARM, business users had binary-only extensions that they expected to continue using.