Naruto is stronger and it's pretty easy to figure that out but Sasuke is capable of fighting him. EMS Sasuke was made to seem equaled to BSM but Naruto was never at full power either times he went EMS yet Sasuke shown jealousy towards that power. Naruto had to get chakra from Yin Kurama both times he went BSM because Yang Kurama was out or low on chakra. Naruto gets gets even stronger with Hagoromo's powerup and then got another powerup in the form of full Kurama and Hashirama cells.
Going off of both Characters past characteristics and training styles; Sasuke wouldn't make full use of the Rinnegan as other users while Naruto would train to be able to use his power the best he can. With the Sharingan, Sasuke did not take advantage of the Sharingan's copying ability; Kakashi learned multiple elements to increase the amount of jutsus he can copy. Sasuke stayed with the same 2 element he had in part 1 and didn't make use out of one of the best aspect of the Sharingan. He didn't really train in genjutsu in the same degree as Itachi; he used MS to control someone in the cloud village instead of just needing the 3T. So I don't see Sasuke full making use of the Rinnegan's ability to use all 5 elements which would let him copy many jutsus which he show no interest in doing.
Another thing is, Sasuke doesn't really have anyone to train with or at least not that many; you could count Orochimaru, Suigetsu, Juugo, and Karin I guess. Sasuke would train in taijutsu, ninjutsu, kenjutsu, learn to fight with 1 hand, improve chakra control, and master the Rinnegan abilities he wants to master. Naruto have many possible teachers to train him to learn how to use different aspects of his power or skills as he done in the past. Naruto would train in taijutsu, learn to use Shunshin more skillfully, ninjutsu, chakra control, improve SM usage, train in KM, KSM, BM, BSM, RSM; possible teachers or training partners can be Kakashi, Bee, Gaara, A, Gai, and Kurama.