The Soulsborne/Nioh games are not overly difficult. This isn't a har har git gud kinda thing, but if you're struggling in any of these games, dying over and over, getting frustrated, you're honestly playing the game incorrectly. There's a couple of those kinda parts every game, but we're talking about a boss dozens of hours in, or an area 30+ hours in, and by that point you should have the hang of the game and you know it's just a stupid part you gotta keep trying until you get through and then it'll be fine again.
I am not a great gamer! I do ok, but I play games on normal, FPS games are way harder than Souls for me and I've turned a few down to easy. I play a lot of sandbox games like Watchdogs 2/Red Faction Guerilla on easy. The only genre I'm legit good at is the character action DMC/Bayo stuff and those I play on hard/very hard/etc...
Here's my tips of how to play all Soulsborne games. I haven't played Nioh outside the demo but I think this probably applies there as well. Since I just did the first couple hours of Dark Souls III, I'm a good example:
-At first you're lvl.1 or lvl.10 or something. You suck, with your starting weapon it probably takes like 4 hits to kill a grunt enemy and they'll kill you in 2-3 hits or combos.
understand why this is happening. 1. Offense: The reason why it takes 4 hits to kill grunts is your weapon atk power is weak, once you upgrade to +1/+2 or use stronger weapons and upgrade them it'll make a huge difference. I was taking 4 hits to kill grunts with my starting long sword as a Knight. I think it had like 90 atk power or something. I upgraded it to +1 and then it was like 120 and took 3 hits. I found a claymore which started at like 130+ and upgraded it a couple of times and now at like 170 atk power I kill grunts in 1 hits usually when holding it 2H.
Holding a weapon 2H gives 1.5x attack power.So now since I know the range of my slash I just run up and slash once to kill each enemy before they can even do anything. Easy.
The other things that effect your damage output is the stat that scales with the weapon. So if it's a STR based weapon with C scaling, then that 170 damage +2 Claymore will actually be 170 + 40 = 210 damage, the 40 being like 20 points into STR or something. So pumping stats into STR or DEX or whatever feeds your weapon grants bonus damage.
BUT, when you're talking about an extra couple of points of damage out of 170+, is it really worth wasting a stat point on that? Eventually, sure. Plus good weapons will have stat requirements to wield them. However, if you want to add stats into something that will increase your damage output to kill enemies before they can even attack you, it makes more sense to pump stats into ENDurance because often when you hit enemies they go into hit stun and you can keep hitting them until you run out of endurance. So if it takes 4 hits to kill an enemy and you can get 3 in, you'll hit 3 times and then the enemy will hit back and fuck you up. But pump some stat points into endurance so you can hit 4 times and now you can kill that enemy before they can fight back and you'll go through an area of them without losing health which is pretty important because stages are endurance/survival battles between checkpoints.
2. The reason why are you dying in 2-3 is your HP bar is low and your equipment is weak. The latter can be solved as you pick up good equipment from drops of chests, but early on and throughout the entire games, HP BAR IS THE KING. A combo from an enemy that kills you if you have a bit more HP will leave you alive so you can run/roll back and drink your health potion drink and survive. Because the Souls games give you an refillable mutli-use flask HP potion, having enough HP to survive getting hit so you can heal makes things much easier. In Dark Souls 3 HP bar is its own stat with Vigor, I think II was like that but in 1/Bloodborne I think HP is tied to Vit. You want to have an easy time? Upgrade your HP stat/Endurance/Equip Load (vit), do that and you can have strong armor and take hits.
So once you get a weapon with some +1/+2 upgrades and get some stats into your HP bar, you're running around killing things in 1-2 hits before they can hit you and even if you get hit, you take the hits, kill them and then heal, no big deal.
3. At this point the main thing is just to be careful not to get swarmed. Since you can kill enemies before they can even hurt you, as long as you move carefully through the levels and don't rush in on your first time you'll be able to run up and kill each enemy before they can do much damage. Even if your initial combo doesn't kill them (big enemies), often you just need to dodge roll once and then hit 1-2 more times and then they're dead. But if you're swarmed by a bunch of enemies and while you hit one the rest are kicking your ass, you're gonna have problems. So generally try to take on 1 enemy at a time, or 1-2 enemies and always group the enemies in front of you so your weapon hit slashes them all and hopefully kills/stuns them all at once.
4. That's pretty much it. In the Souls games your refillable HP flask will upgrade as you go along and find items. So instead of having 4 potions between checkpoint spots, you later on have 6-8 potions between. So as long as your careful you'll be able to keep progressing further and further refiling your HP as you go.
5. But, bosses are a whole different thing. There's generally a bonfire/shortcut near all of them, otherwise it's just pattern learning and doing damage and healing at safe spots. I like to use high power/damage weapons so I just try to get the 10 or so hits in to kill them before they can kill me. Some Souls bosses are pretty dumb and staying up close to them makes their big flashy attacks go over you so you can beat them up easily. Always good to know. Bloodborne bosses not so much. Bloodborne bosses require more skill imo but I'm sure that's debatable.
Anyhow, even if you follow all that you're gonna die sometimes, but it's not a big deal. I'm like 3-4 hours into Dark Souls III and I still die a couple of times an hour, but it's usually doing something stupid or a new boss/mini-boss and then I get back no problem and grab my souls and do it better the next time. But it's not frustrating because there's always ways to get stronger even without skill and everything gets easier as you get stronger. Every soulsborne game I've played eventually when you get a +10 max upgrade weapon you're ridiculously overpowered and it's pretty easy although Dark Souls II balanced it the best out of De/DS1/BB and still had some real tough stuff in the endgame.
But yeah, these are great games and honestly they are for everyone, but you gotta learn how to play them. If you don't know what you're doing and your playing them wrong with lvl.1 weapons and low endurance/hp, it'll just be frustrating and unfun. Once you get the hang of one though, you're set for the whole genre and it opens up a ton of really fun gaming. Lots of cool exploring in all these games and neat secrets everywhere. Just don't rush on 1st look at an area and you'll enjoy. On 2nd time in an area though (like if you died and you want to get back to your souls) you can pretty much speedrun most areas since you know where the encounters are and which ones you can avoid and just run past.