Board Thread:Versus Debates/@comment-30168027-20161222142720/@comment-25122992-20161225175823

Nope, the Biju chakra wasn't required for calling Hagoromo. Naruto met him in the subconsciousness even before remaining Biju chakra (Gyuki, Shukaku, Yin-Kurama) was sealed in him by Obito. Also, Hagoromo admitted that Naruto possesses some special trait which was the reason why he could appear before Naruto and why Asura choose him as his reincarnate.