There's a playstation 1 game from around the early 2000s. It was a 3D game where you played as an character who looked like an egg. All the other character also looked like eggs and were all very colourful with patterns like polka dots. The game itself was a grid that you moved through to get from one screen to the next. I think sometimes events like dialogue happened when you moved between screens. The game was also very colourful and I remember there being a lot of green.

Sorry for the vagueness but I have never played another game like it since!

Thanks