Central Ohio is hands down a combination of Thomas, Neel #1, Sparrow, and Farrington. There are others that grow and perform well including Ohio, Emma K, Rohwer, Football, etc. For one reason or another I would cull all of them. Sparrow is highly productive and is a protandrous early pollen producer. Other than that, Sparrow is a small nut that takes more time to process. I have about 40 varieties of black walnut grafted with most around 20 years old. There are plenty more varieties that I do not have experience with.
The rarity with walnut is a tree that branches prolifically. The more a limb branches, the higher the production potential. The most prolific branching varieties I have are Thomas, Football, and McGinnis. Football has a problem with filling the nuts often making a huge crop of slightly wrinkled kernels. It shells out beautifully, but the kernels are not very appealing to look at and the flavor is poor. McGinnis is a highly productive tree that branches abundantly and makes a small very high quality nut. It is an outstanding variety in northern climates for which it is adapted. Thomas is arbitrarily the best of the old walnut varieties with high production and excellent quality nuts. The only significant flaw it has is that the shell is thick and it runs 22% to 25% kernel. Other varieties produce higher percent kernel.
I’ve had time to observe more varieties over the last 10 years which is why I now suggest Farrington as a very good producer. I get a crop every year from Neel #1, Farrington, and Thomas. Others tend to be biennial producers. Black Walnut named varieties - #15 by Fusion_power