Somebody asked in the Corsair forum if the Corsair sleeved cables for AX850/750/650 are compatible with Seasonic Platinum 860W, I replied to the thread, but Corsair deleted my post.
I purchased the Seasonic Platinum 860W PSU and the Corsair Sleeved Cables for the AX650/750/850. I installed and found the 20+4pin power cable is compatible. One of the 4+4pin power cable is compatible. The PCI-E power cables are compatible.
One of the 4+4pin power cable is not compatible. The SATA power cables are not compatible. The Molex power cables are not compatible. The square and cornered pin positions are correct, but the Corsair cornered pins are facing up and Seasonic cornered pins are facing down. In order to make it work, you have to extract the cables off the Corsair and put them into the Seasonic plugs.