The characters movement and movesets are similar to the Nioh games but it plays quite differently. ROTR emphasizes the parry mechanic much more, especially on its hardest difficulty levels. So you are constantly trying to stagger enemies by parrying them, which then opens up a 2-3 second window to retaliate
When it comes to difficulty, I found that if you do everything on the map you can be quite overleveled about midway through. This can make the more common enemies easier, but the difficulty spikes are still there with a handful of bosses that make you want to punch through a wall. The game gives you "allies" to fight with(if you choose), but in my experience, it is a mixed bag whether that makes the game easier or harder. The health pool, damage dealt, and aggressiveness of enemies is massively increased when you have allies fighting alongside you, and I found some fights easier and some fights harder depending on the boss. I tried to just solo everything for the most part, except for duel boss fights. Overall, it is tough game, but not as tough as the Nioh Games, especially if you do all of the side content
FYI, played on the hardest difficulty(twilight)