It's not that difficult to figure out.
Assuming apples to carrots...
A current Skylake cpu sports around 1.35 billion transistors at 14nm.
An 8086 sports around 26,000 transistors at 3 microns.
NOT accounting for anything else other than equivalent transistor counts, you should be able to fit just shy of 52,000 8086's into a Skylake die.
Keep in mind that the 8086 itself was designed around a completely different process and methodology, so things like white space and simple architectural differences would need to be accounted for if you're talking about putting actual unadulterated die-shrunk 8086 dies onto a Skylake die. But regardless, with any process change the actual design of the logic layout will have to change to accommodate the new process anyway. So apples to carrots...