Guide:
Northern Deshaan, east-northeast of Mzithumz Wayshrine, east of Mzithumz (broken tower icon).
Start at Mzithumz Wayshrine and follow the road above it to the east. There are many hostile NPCs in this area, so be careful. As you follow the road you will eventually come to a building carved into a cliff. The skyshard is slightly to the right of the entrance into this building, surrounded by broken stone blocks.