I've played a fair amount of games and so far I'm really liking this meta. From the games I've played I've observed that Marshadow, Magearna, and Zygarde-Complete are all amazing in this meta.
Marshadow can hit so much in this meta and has made most setup sweepers disappear. Technician + Shadow Sneak is so good for revenge killing. I've personally been using Sash Marshadow and it's been pretty nice. Being able to take a hit really helps Marshadow out.
Magearna is great since it's on of the few mons who can take on Zygarde-C easily thanks to Fleur Cannon (or Z-Fleur Cannon). It also has insane coverage and it really versatile. There's so many different sets it can run: Trick Room, Shift Gear, All-out Attacker... the list goes on and on.
Zygarde walls so much in this meta, the most important being Marshadow. I've been using a phydef set with 252 hp/ 252 set with Thousand Arrows, Glare, Rest, and Sleep Talk and it can tank hit after hit, even from some special attackers. This thing is really good and should be on every team imo.