Go inside Aba-Loria solo dungeon to pick up this shard. Entrance to this dungeon is at the end of the northernmost main road in western Coldharbour. It looks like an Ayleid Ruins area. Enemies inside are level 45 Salaches that come in groups of three.
Collectible is inside a corner of a small room in western dungeon room, next to two small bookshelves.
Find and enter Aba-Loria solo dungeon.
Dungeon entrance map
Once you enter Aba-Loria solo dungeon keep going to your right.
Dungeon collectible map location.
Sand Kingdom Moons - Super Mario Odyssey Power Moons