I don’t remember the exact release date but it’s between 1997 (as the first Harry Potter book was published that year; in the DVD cover it mentions it in the tagline/“review”) and 2010 (year I watched).
It’s children or family drama/fantasy oriented film about kids going to a haunted place. I don’t remember exactly what place was but it was a dark building in the middle of a forest. Inside the building it lived a couple of vampires, which sorry not sorry, they were kind of Addams family knockoff, and likely lived other creatures too.
I recall the children going by bus and the destination tag changing from school/whatever town to the spooky place.
There was a girl who befriends a boy and makes a blood pact with him, which later they use the gesture of the hands as symbol of trust. The cut was made on the hand and the gesture resembles of a butterfly/bird.
About the third act the girl was in danger and the blood pact boy saves her, which turns out he’s a werewolf.
I’m not sure, but maybe it was a direct-to-DVD movie. I can’t say it’s a “hidden gem”, even my child self felt it was mediocre. However, I don’t know objectively as I never searched for reviews for this movie.