The post-operative picture on the left shows recipient area necrosis (a loss of blood supply to the graft area). This area healed with the scar that you are showing in your 6 months photo as I would have expected (photo to right). You need another hair transplant to fix this. You should ask your surgeon to make it right for you as this reflects a surgical problem.
You should never select a technology. A technology is only as good as the doctor who uses it. I have seen disastrous results with good technology. Instead, you should find an outstanding surgeon who has performed many FUE procedures and sees his patients by meeting them one-on-one, as I offer in my clinic to all prospective patients every month.
It depends on the cause of the woman’s hair loss. If the woman had miniaturization of the donor hair, then this hair may not last a long time. If the donor hair is normal, it should last a woman’s lifetime. Many women with genetic balding have miniaturization in the donor area and, when this is more than 20%, I consider that woman not to be a candidate for a hair transplant. The miniaturized hairs may not last, and any woman asking for a hair transplant other than a hairline lowering procedure should ask the doctor to evaluate the donor area for miniaturization.
This is an interesting article. What seems to be missing is more on the Radiofrequency hardware that they are discussing, and the full article is not available from this link.
https://www.ncbi.nlm.nih.gov/m/pubmed/29952106/?i=1&from=Microneedling
Yu AJ, et al. Clin Exp Dermatol. 2018.