Juniper Mae: Secrets of the Guardian Knights by Sarah Soh

Deep in the forest, Juniper Mae and her best friend Albie are working hard to become Guardian Knights. When they're not helping the tama-tamas with amazing new inventions, they're discovering ancient artefacts, training to fight evil, and learning more about their ancient knightly heroes. But a great darkness is rising close to home, and when one of Juniper's latest inventions creates a rift between her and Albie, they must find a way to work together to take the latest evil down and save their beloved forest.