Having not read it, I cannot say for certain if British author Jean Flitcroft's new young reader book series The Cryptid Files falls within the same category as the aforementioned two, but I've high hopes.
Revolving around Vanessa, a 12-year-old Irish girl seeking to complete her mother's quest to uncover the mystery creatures of the world, the first book kicks off with a quest for Nessie. Instead of taking chapters to head to Scotland, the story begins fast with a gripping prologue where the girl ends up deep in the drink of the loch. The same pace is again set right away with the as-yet unreleased follow-up featuring Chupacabra.
The book has yet to be published in the United States just yet, but it can be found through Amazon. If you've kids, or just a cryptid fix, check it out.