The text is rephrased using models fine tuned to minimize the score returned by GPT detectors.
It depends, if the size is too big you will get an error, try to split in smaller parts
Most commonly used languages are supported: English, Italian, Japanese, German, Spanish, Portuguese and more.
There is a free plan with 1000 words per month, then you can buy more credits or subscribe to a plan clicking the "Increase Limit" button.