There are three of Wanda's journals to be found in Sea of Thieves. One is on Mermaid's Hideaway, the other is on Thieves' Haven, and the third is on The Sunken Grove. Each of them has a little story where you can read about Wanda's experiences with the Cursed Cannonballs, which were introduced in the Cursed Sails event update. These newspapers are always available for you to find and read.
Mermaid’s Hideaway
You can find Mermaid Island's Hideaway at coordinates B and C 13. When you get to the island, head to the center of the island to find an NPC named Five Paces Frank. The newspaper is right next to him by the campfire.
Sunken Grove
The next log is also near the center of Sunken Grove Island, which you can find inside a small cave tucked away. There are no NPCs nearby, although there are a handful of bones and broken items around the location.
Thieves' Haven
The last journal is on the east side of Thieves Island. Go to the beach in the northern part of the east side and look for a cabin. It should look like a wrecked ship turned into a small house. The newspaper is next to the dead campfire.
