* Mewtwo cannot breed: It's a legendary Pokemon and specifically designed to be unable to breed.
* Ditto can breed with anything: It's a special Pokemon that can transform into any Pokemon and breed with it.
So, technically, a Mewtwo and Ditto can't make anything. They can't breed.
However, in the world of fan theories and speculation:
* Some might argue that Ditto's ability to transform into Mewtwo could somehow lead to an offspring: This is highly unlikely, as the game mechanics don't support this.
* Others might imagine a fusion of Mewtwo's power and Ditto's adaptability: This would be more of a fictional concept than a real breeding result.
Ultimately, it's a fun question that opens up possibilities for imaginative thinking about Pokemon!