Sekiro
So far I'm rather underwhelmed by it to be honest. From kept all the things that made their previous games hard (hard, erratically hitting enemies, punishing deaths, low vitality) and thrown out all the things that made overcoming said difficulty so fun and rewarding (awesome loot, weapon variety, build variety, loads of approaches to tackle different situations, intriguing level designs with loads of hidden nooks and crannies)
What remains in the end is a fairly basic action game (compared to the likes of DMC, Ninja Gaiden or Bayonetta) that feels unfair more often than not. Imagine a DS game in which the only way to proceed was to parry and riposte all damn day. And just like in DS, one or two botched parries send you back to the latest bonfire. Learning from your mistakes becomes damn near impossible when there's literally no room for error.
Update: starting to get the hang of it. Still, there's a couple too many instances of leftover crap from the Souls engine messing with your shit here. Like a rather unreliable lock-on feature and camera problems. That stuff was part of Dark Souls and Bloodborne as well, but Sekiro's heightened focus on reading enemies correctly at all times exacerbates those issues greatly.
Update: game finally started to open up. Now I have the choice pf plenty of different walls to bash my head against instead of just the one
Update: almost done with it. Final boss and a couple of optional ones are still waiting to be taken down, but other than that I mopped the floor with everything the game has to offer.
Game is a tough one to master and not exactly flawless (the camera is gonna kill you time and time again), but it's incredibly rewarding. Not From Software's best, but a damn good game in its own right. Due to its surgical, single-minded approach to combat gameplay I suspect it's gonna lack in replay value. You cannot really build different Shinobis here. On the other hand I finally got why the game is so damn challenging: it wants you to master its combat system in order to be successful. That wouldn't be entirely neccessary if the game was easier.
Right now I'd rank the From games as follows: Bloodborne = Dark Souls > Dark Souls 3 > Demon's Souls = Sekiro > Dark Souls 2.