The Little Mermaid References
This easter egg is seen during the "You're Welcome" song.
When Maui is singing the “You’re Welcome” song to Moana, he takes her to a 2D world where we see a school of cartoon fish swimming left. When the school begins to swim upwards, on the right side of the screen you can see Flounder from the Little Mermaid.
During the ending credits when we see Tamatoa, the giant-treasure hoarding crab, he is still stuck on his back and tries to ask the audience for help to get flipped back over. He then states, “Can we be real, if my name were Sebastian and I had a cool Jamaican accent you’d totally help me. You would, you know you would.”
This is an obvious reference to Sebastian, the famous red Jamaican crab from Disney’s The Little Mermaid.