You can feed them more fertilizer, epsom salt , and Water and see that it get better.
It might not be FMV mites, you need to prove them using x50 loupe, My potted fig trees have some leaves look like your because of FMV mites, However, I am in Canada, where I can not get powerful pesticide to treat them, I can not get neem oil , very sad to see those FMV mites hurting my fig trees, I will leave all fig trees outdoor this winter with sulphur/lime treatment and hoping that cold winter clear all mites.
Epsom salt is not treatment of FMV mites, FMV mites is very strong mites even stronger than spider mites, it needs long lasting pesticide to clear them and those pestcides are banned in Canada due to killing Bees. There are many bees in my garden now, I wish that I can get neem oil to treat my trees and it is not allow here as well.