If battery life is what you're after, looking at a 1.5 generation (soon to be 2.5) old 35W Ryzen that gets 11 hours of battery life should give you clues. Ryzen 7000 mobile should be announced in January, and those will utilize TSMC 5nm.
That's a pretty bold claim that you're going to need to back up. AMD has been beating Intel in performance-per-watt for years now, and both are regularly trading blows when it comes to fastest consumer chip.
And that's not even talking about EPYC which is pretty thoroughly trouncing Xeon in just about every metric.
