Not really knowledgeable on whether Sasuke got exponentially stronger as it pertains to the Shinden light novels, so I'mma go ahead and say Toneri, seeing as he was casually splitting gargantuan stone spheres like the moon, and physically pressuring KCSM Naruto in Close Quarters.
Sasuke's 6T Rinnegan Susano'o is implicitly inferior to EMS Madara's as it garnered no where near the hype, or manifested the unique blade properties ie., PS Shockwaves, although it currently possesses the superior destructive features, we are not explicitly privy to EMS Madara's upper limit as it pertains to his Perfect Susano'o.
Hence at best it's <<</= EMS Madara's Perfect Susano'o.