I want to say Death wins here. I haven’t really analyzed his feats, but scaling above Puss on its own might be enough here given at the beginning of Last Wish Puss KOs a forest giant without much effort.
Also given death is literally the concept given form and the end of the movie pretty much says Puss could not actually defeat death, just delay him by accepting his mortality and treasuring his last life…
I’m doubtful Death could be killed by normal/physical means.