Its...good enough movie. Too bad its not based on lovecraftian like the first one. Instead it is based on witch-devil-God conflict. Although God isnt prominent here like in Constantine.
The action is okay. Less drama than the first one. Lots of characters were introduced and killed off. Not enough explanation for the 3 MCs (Hellboy, spirit lady n special op guy). Not enough backstory for the organisation nor for Professor Broom. Little explanation about the witches and what happen after Nimue (the antagonist) was sealed. Nimue's sidekick was comical and despite him murdering bunch of people, theres little tension going on. And the large use of CGI blood make all the killing scene to feel...less realistic.
But, who cares about that. At least explain what is what and who is what in the movie. For example, at the end of the movie, we learn that Broom was a good fighter, but thats it, theres no indication about it in the whole movie.
The plot feels...rushed.
If theres a star rating system of old, I'd rate it 3 out of 5.