If you like the Cryptid Hunters by Roland Smith
I've included three titles below that I hope you might enjoy.
The Secret of Platform 13 by Eva Ibbotson.
Odge Gribble, a young hag, accompanies an old wizard, a gentle fey, and a giant ogre on their mission through a magical tunnel from their Island to London to rescue their King and Queen's son who had been stolen as an infant.
A Wrinkle in Time by Madeline L'Engle.
Meg Murry and her friends become involved with unearthly strangers and a search for Meg's father, who has disappeared while engaged in secret work for the government.
Gregor the Overlander by Suzanne Collins.
When eleven-year-old Gregor and his two-year-old sister are pulled into a strange underground world, they trigger an epic battle involving men, bats, rats, cockroaches, and spiders while on a quest foretold by ancient prophecy. The first in the Underland Chronicles.