He didn't lose anything in the movie
He doesn't have Rikudo Mode because he doesn't have any sage chakra left probably after releasing IT same goes for Sasuke he doesn't have sage powered chidori anymore U_U
Says Naruto lost Rikudou Mode, yet we've confirmed that Naruto never lost the power.
Knowing full and well Sasuke's Sharinngan is not implanted in his own body, it is forced activated due to him having Sage chakra. As Sage chakra allowed him to gain the rinnegan in the first place, it was never attainable through him having Hashi cells (As Madara waited a long ass time) and not through just him being Sasuke. It was due to Indra's chakra that manifested in a young boy named Sasuke who gained a rival named Naruto (Ashura).
Not to mention most of spoilers (and Lost Woods who had seen the movie) said Naruto displayed Sage-like powers towards the end of Toneri's battle.
It's pretty simple to say they never lost the Sage's chakra as the Sage himself was still manifested in a ethereal form, and could use his own chakra once summoned by all of the Tailed Beast entering Naruto (as he was the one who connected Hagoromo to himself by finally bringing them all together).