I enjoy Hellboy so much that I’m considering reading more Dark Horse comics instead of the usual Marvel/DC duo that I’ve pursued before.
I may also take up reading Dark Horse Manga if I can find the right work that doesn’t offend me.
The The League of Extraordinary Gentlemen books might help fill that niche.
Check out Savage Dragon from Image.
I remember Concrete from Dark Horse in the 90’s. That was a great comic.
I’m working my way through Hellboy now and already wondering if there’s anything similar for afterwards. It’s extremely well done! Have you read all of the BPRD, Abe Sapien and Lobster Johnson stuff?
Maybe I should, because I enjoy it too.
Exhaustive reading order chart on this website: http://www.multiversitycomics.com/annotations/hellboy-reading-order-2023/
Not Dark Horse but Atomic Robo is something you’ll probably enjoy if you like Hellboy. The author also puts the comics on his site for free so you can get caught up.
The Red Sonja stuff from Dynamite is really good. Much different time period, but still a great book.
East of West
I never read Hellboy, but would recommend East of West in nearly any context.
Brass Sun by Edington and Culbard (Rebellion).
Lady Mechanika are excellent comics somewhat about the supernatural kind of like Hellboy, and also including some Steampunk.
Hellboy pulls from a lot of European mythology, so you might be interested in the things Charles Vess does.
Artistically? About as different from Mignola as you can get.
Thematically? Very similar.