If youve unlocked the heritage armor for that race, you should get the option for that race to skip the starting zones and go straight to level 10, like allied races.
Blood Elves would start in Silvermoon, with a quest from Lor'Themar and a portal to go to Orgrimmar and start the Battle For Azeroth campaign. Obviously still with the options of Sunstrider Isle and Exile's Reach.