Generally most review sites compare CPUs in a similar price range for the tests that they run, but now Intel has what used to be $1,000 - $2,000 Intel CPUs going up against AMD CPUs that are half this price. So I can't say if a former $2,000 Intel CPU will out perform a $900 AMD CPU. To make things more complicated AMD has their new line of Zen 2 Threadripper CPUs coming out in November which might swing things back to AMD's favor. The one good thing is that CPU prices will be a lot lower with competition like this.
anyway i have finally tried h265 4k files on my laptop(it was for service) which has i7 7700 gtx1050tiand 16gb and i can play fine all the files. In premiere little struggle, i need to render them as soon, but since this i can say that it shouldn t be so difficult to work fine with a new pc, without th eneed of latest specs.
So as thedingo suggest, a ryzen 7 3700 or a i7 8th generation would be fine without thinking too muche about ..
