Inside Sanguine’s Demesne public dungeon. Start at Stormhold Wayshrine and follow the road to the east ending in the hills. It will lead you straight to the entrance of Sanguine’s Demesne. Once inside, follow the eastern path. Be careful, this dungeon has big, hostile, NPC packs with number of mobs sometimes reaching 6+. Continue clearing until you arrive into a cave room with water running through. As you exit the tunnel you can see the skyshard surrounded by inscribed stone blocks.
Road will lead you straight to dungeon’s entrance.
Entrance map location.
Inscribed stone pillars surrounding the skyshard on the left.
Skyshard location on the dungeon map.
Sand Kingdom Moons - Super Mario Odyssey Power Moons