Mazatrol to G code.... Yes. Many, many ways.
G code to Mazatrol.... I've never seen it. The only way I know of, is if you have the G code in Mazak's 3-digit format. Then yes, you can convert G code to Mazatrol simply by loading it into the control.
Conversational requirements are a bit different than G code. It's not as "random" as G code can often be. So a good, accurate translation would be tough. But then, Mazatrol is so easy and quick to program, I think the thought is "why bother"?