i only experience this on Chernaruss and the only solution i found, just turn off the shadows in your grafic settings. sadly i don't know what causes it.

So I found out how to fix this temporary. You need to enter an Altis, Stratis or Essecer Breaking Point server, spawn your character, exit the server into Arma 3 main menu, then press Play, enter Breaking Point in server Filter, choose any Breaking Point Chernaruss server and enter password "breakingpoint". It fixes all the textures, but when you close the game, bug reappeares and all of this must be done again to fix those black textures.