GPT isn’t really designed for translation. It’s designed for text generation, and more specifically, text completion. That’s a conversation for another time, the difference between text completion and generation.
Now, what you could use GPT for, is the cleanup phase. You could do something like take each paragraph translated from Google, and give it the two paragraphs ahead of it two of the pre-edited paragraphs before it and another two after it. Then you can give it a prompt like: “Rewrite this paragraph for clarity to a 21st century American PhD holder.” Or maybe for a high schooler. Or a fifth grader.
GPT actually does do very good at that sort of task. But translation itself? Nah.
Source: I actually use these tools for this sort of purpose