Pokemon: Pikachu's Rescue Adventure (1999)

Ash, Tracey and Misty are tired and settle down for a mid-day nap. All the Pokemon take a nap also. Suddenly, a flock of Ladyba fly by and awakens Togepi. So entranced is she by the sight of them she follows them. Togepi of course does not pay attention to where she is going. She falls into a hole and enters a magical Pokemon world. Pikachu awakens and finds Togepi gone, and immediately sets out to find her. They follow her down the hole she has fallen into and Pikachu's Rescue Adventure begins. There we see all kinds of Pokemon gathered together. They all help Pikachu and friends to help find little Togepi. This wonderful little adventure is entirely in what I like to call Poke-speak (with the exception of beginning and end very briefly Ash and friends speak). Otherwise, it's all about the Pokemon.