If money is no limit, the obvious answer would be a Nikon Z8.
If sheer AF capabilities are the priority regardless of the system, it wouldn't be Nikon but the Sony A9 III.
If it should be a combination of reasonable costs combined with good AF and Nkon, you should wait for the Nikon Z6 III which should be coming out very soonish.
Forget about DSLRs - they don't have subject detection AF.
But there are shades of grey here - what are "advanced autofocus capabilities" in your book?
