Does anyone have any experience with planting Moringa near Black Walnut?
If not I'll plant some and see and post results.

I'd venture to say that it is an open question. One of those trees needs climate zone 10 or warmer, the other one needs climate zone 8 or cooler. If you have the moringa in a pot (so that you can take it in for the winter), then it is not going to have a problem with the juglone from the black walnut.

They both need very warm climates.
MORINGA STENOPETALA is a little more cold tolerant but not much. A ground freeze will kill the roots.
Recommend growing a few in a greenhouse for seeds and growing several outside as annual for leaves only.

The black walnut will grow in zone 10+ if you plant it there but it will not really fruit. Because they are from different ecozone They will most likely not affect each other.