Yamato's Cover Series is pure Act 4 set-up, and for fans of Yamato/Wano. Yamato gathering a group of Beast Pirates to defend Wano will let her leave the island eventually, after Teach comes.
The funniest part of this is if Law/Bepo did go to Zunesha, like I think, there's a good chance Teach and Law meet again. I could see Teach selling Law to the Underworld to execute; the Underworld should hate Law after he took down Doffy, then Kaido.
If there's no Blackbeard invading at the end of this, then this Cover Series is one of the worst, definitely. Sometimes I wonder if the Cover Series would be better as 4-Koma panels...