As seen here Sasuke got transported to the desert
There's no way for Sasuke to escape that desert
, none at all. He can't go back
to where Naruto is. He can get soloed by Black Zetsu anytime now since Naruto isn't there.
The poor kid is going to have to face Kaguya and Black Zetsu on his own that to at half of his true power
since other half is protecting Obito, Kakashi and a fodder!!
Had it been Hiraishin user, he'd have teleported back to where Naruto was in an instant!
Kaguya would've had no way of separating them!
She'd be forced to take on the pair no matter what