Puzzles, Secrets, and Hidden Chests in Dragonspine

Final spot is outside of Dragonspine, in around Mingyun Village area. Head to the spot shown above, and find the wooden plank near the trees to dig for the treasure.

Outside of Dragonspine area, on the other side of the mountain, there are activate-able elemental pillars. Shown above is a Pyro pillar, close to where Bennett is standing. The black arrows are pointing to 2 other Electro pillars that you will need to activate. The pillars have a short timer, so you will need to turn all of them on pretty fast. It's easier to do using Amber for the Pyro pillar, or just Fischl for the 2 electro pillars.

The white arrow shows a common chest, blending in with the bushes.

Northern Dragonspine, in the spot marked above, you can find 2 treasure hoarders on a bridge. There is a treasure chest just below the bridge that you will need to melt with a Pyro attack.