How does this compare to Bloodborne and DS 3?

Hell yes, this game deserves every sale it gets. If you haven't played it yet give it a shot; this is a masterpiece.

Well deserved, it's an amazing Game, Goty contender.

Well deserved. One of the best games this gen. I am finally almost done with my first playthrough. .

It's hard to say because, while the design philosophy is very similar to Bloodborne and Dark Souls, it's not a lot like those games. It's punishing, it has the same healing and checkpoint system, it has the same world design, but beyond that it's not too similar. 

Rather than having multiple classes you just get Shinobi, rather than levelling up stats you get skill points to spend on passive abilities or new moves (though you can find items that can be exchanged for health or strength or defense buffs). Plus the story is a bit more straightforward than Dark Souls/Bloodborne since you play a singular character rather than a create-a-player. I would say that the combat is the best out of the above discussed games, it's also got the highest difficulty setting (with options to make it harder), and a lot more mobility in regards to jumping and the grappling hook. 

I personally like Bloodborne more and I'd say Sekiro is on the same level as DS1 or DS3. 

i Remember Bloodborne Sold 2 Million After maybe 6 months

Dark Souls 3 sold 3 Millions After almost 2 months

Sekiro is doing Really Really Great,Well deserve

You see? This game is doomed without an Easy mode.

Major difference in Sekiro is the lack of a stamina bar. You can now swing and dodge as much as you'd like, but you can't stunlock enemies like in a Souls game (where once you get the first hit, you can keep swinging until you are out of stamina, depending on the enemy poise stat).

Instead, you have what is called a posture bar, which starts out empty and fills up as you take damage and block attacks without a proper deflection. If you time your block perfectly, you get the aforementioned deflection, which causes the enemy's posture bar to fill up instead of your own, and you can get the opportunity to go in for an attack depending on the situation.

Your posture bar will recover slowly on it's own, and quicker if you are holding a block stance for an extended period of time. Also, some abilities influence posture.

No more soul levels, and this mechanic has been replaced by an XP system which allows "level-ups" to provide you with skill points to unlock new talents and skills. I personally prefer the Souls style of level-ups, but Sekiro has a more simplistic and accessible approach. Perhaps they did this to keep most players at a similar power level so fights can be balanced much better. But that's not to say that there is no progression at all, as there totally is; it's just a much more gradual increase.

Stealth is also a new mechanic to the genre, and it allows you to sneak up and backstab enemies for an instant one-shot death in most cases. Some enemies require two of these "deathblows". Sekiro is much more agile than the heroes of past soulsborne games, as he can freely jump, wall jump, grapple, swim, and fall large distances.

If you enjoy the genre, Sekiro won't disappoint. Amazing, amazing freaking game.