This shard is at the bottom of the large Valeguard tree. It is rather easy to spot if you approach Valeguard from the main south road. It stands in a corner, between a huge tree and nearby mountain rocks. If, for some reason, you reach Valeguard from north, and start climbing to its top, you can miss it without even noticing. There is a rather large bridge that almost completely covers this shard from above.
Approach Valeguard’s tree via the south road.
It is far easier to spot the collectible in the corner, when coming from south, than from the tree bridge above, when coming from north.
Sand Kingdom Moons - Super Mario Odyssey Power Moons