This is Owen’s Wishing Well which is located in Tidemist Thicket in the Jade Forest. It was made for a boy named Owen who was diagnosed with cancer when he was 14. He used his make a wish trip to visit Blizzard Entertainment and they made this for him. He passed away when he was 16.
A Lucky Golden Coin lays on the well and it will give you a buff called ”Made-A-Wish” when flipping it.