Halruaa is back, but changed. How? Up to your DM until 5e official coverage comes…but lingering Spellplague effects would have ravaged the minds of some spellcasters and much that was built with magic in Halruaa.#Realmslore
— Ed Greenwood (@TheEdVerse) February 28, 2019
Any notion of when 5E official coverage will come? None whatsoever. It's outside the Sword Coast area, so it could be a long time, if ever.
And if I did know, I couldn't say (NDAs would forbid, linked to the longstanding policy of TSR and now Wizards of not discussing future products).— Ed Greenwood (@TheEdVerse) February 28, 2019