On the whole, the film's gore is a notch above what was in Princess Mononoke. People get cut down, shot, impaled, and there are a couple instances of dismemberment, but it never feels like the film is going for an unrealistic amount of violence for the film's setting and story. And around half the film is calm moments without any action or violence, so it gives you room to breathe even if the action scenes get a little intense at times. There are even one or two fights that end with barely any visible blood. I personally found myself more uncomfortable with Tessai's scenes in Ninja Scroll than I did with almost anything in this film.
I think you should watch it yourself and see what you think. I personally didn't find it a whole lot more violent than Princess Mononoke, and since you have that film favorited, I think you could handle Sword of the Stranger.
Let me put it this way: Sword of the Stranger is a samurai film, so it does have a pretty high death count, blood, and a fair amount of gore. It's a movie with a lot of fighting and conflict. However, unlike Ninja Scroll, it doesn't feel like it ever goes out of its way to be as gory and nasty as possible. It's more grounded. You don't see things like a woman with a snake in her... you know. You don't see anything like a big guy who can turn his skin into stone ripping off another man's arms and drinking his blood, and heck, there's nothing quite like the way said rock guy was finished off in the entire film. Sword of the Stranger, overall, goes for more realism, whereas it seemed like Ninja Scroll was going out of its way to be nasty in parts of it.
I saw your comment on the Ninja Scroll page, and I had to ask... have you ever seen Sword of the Stranger? I'd recommend it. In my eyes, it's a more compelling fast-paced and suspenseful sword-action-type film than Ninja Scroll. It's also pretty violent, but it doesn't go into the level of gruesome detail that was in Ninja Scroll and the mood of the film isn't nearly as overbearingly grim (it also doesn't have any sexual imagery or nudity, either). It balances out the intense action scenes with light-hearted scenes involving two main characters that are far more likable than the characters from Ninja Scroll, and it has more heart at its core. It also has better animation, better music, and the story and pacing flow much better than Ninja Scroll, IMO. It has an excellent dub, too.
Hey, I found your YouTube channel and your anime dub review blog. Your dub reviews are spectacular and I especially loved your Fullmetal Alchemist dub review. I pretty much agreed with every single word you said there, and I loved all the detail you went into.