There will be no raiding required. Some people may have seen the requirements on the PTR and we do plan to talk about them more to help spread the word.
As it currently stands, if you do the Zandalar quest arc (through the Blood Gate quest and Zul’s death), the War Campaign through the Tides of Vengeance achievement, and get Exalted with the Zandalari Empire, you will be able to do the questline to get access to the Zandalari Allied Race as soon as 8.1.5 goes live.