I have heard of Moringa. For the most part, however, and with very few exceptions, I try to use plants from my own bioregion (the Mountain and Desert West of the US).
Some exceptions are:
Maca, an Adaptogen from South America,
Ginseng, because North American ginseng is nearly extinct,
Dong Quai, because I don't know how to cure our local Angelicas,
Wild Yam, (from the forests of NE US), because local alternatives are heavily stressed,
Superfoods like Moringa are amazing, but one thing I have found is that one's ethnicity can make a big difference in the efficacy of a medicinal plant. For instance, Inmortal, a desert Milkweed, was used by the New Mexico Spanish for bleeding after giving birth. It works well for latina women, but does nothing, and can have scary cardiac side effects, for blonde, blue-eyed women. There are many examples from this area as well. I am sure there aree examples from other places, too. For this reason, I am very careful about the many fad plants being introduced as miracle cures (not saying Moringa is a fad). Each person's individual constitution can change what does and doesn't work as well. What can cure one person's cancer may make another's worse. This is why seeing an herbalist for major problems, instead of just googling something, is so important. Besides, most herbalists are cheaper than their MD counterparts. I have sometimes wound up treating problems that really should have been shown to a doc because the client could not afford medical treatment.
My usual advice is this, try a few simple things for your problem. Give it enoigh time to work. If you can, get diagnosed by a doc. If simple things don't help in one or two months, find a local herbalist for help. If they are honest, and the problem is beyond what herbs can do, they will tell you so.