Agree with the high clocked 8C part. That was one I predict to be the highest clocking part, but (2) 4C chiplets binned for the highest clocked cores and with the greatest area of silicon to dissipate heat.
A 50th anniversary special edition?
I think you will find the clock potential being hire on single chiplet, CPU over a dual Chiplet. It should be less of an issue but on Zen 2 because of less of other stuff. But generally turning off cores out of die don't generating the savings people estimate. Finding a really good cherry single chiplet with full power allotment is going be a much better option.