Both are supernatural slice of life featuring a young protagonist who helps Youkai/Ghosts while she/he learns the worth of bonds, family and friends in daily life.
Both are very heart warming manga. However, YZtM is more focused on romance while NY is more focused on friendship.
YZtM: A ten year old girl is able to see the spirits of the deceased. She tries to help them in her own way.
NY: A teenage boy is which is able to see spirits. He tries to help them with everything in his power.
When I started reading Pinocchio, all that was similar between these two was that the MC could see ghosts. In YZtM it was her ability while in Pinocchio she could see one because of a necklace. The real similarity came after a major plot twist, or should I say that the plot twist is the same in both. Overall really beautiful stories you'll surely enjoy them
Both mangas have a focus on the supernatural and relationships with loved one, there is slight romance in both but it isn't the most important part of the story as well as comedic relief. Both story lines are beautifully written.
Both have as main protagonist, a naive energetic girl who does everything to help others. She is protected by a supernatural best friend[in Kobato is a stuffed dog from the other world, in YZM is a ghost, and in both stories, the guy doesn't show her his true form]. There is also a female teacher who is very close to her, and a boy that at the first despises her but later becomes her ally.
Both are very tender and sweet stories with slice of life and supernatural events.