I’ve run into that same problem, especially when I was helping a friend polish a travel blog she wrote in Spanish. Every time I rewrote a sentence, it either turned too formal or lost the mood she originally had. What ended up helping me was reading the whole piece out loud before rewriting anything -hearing the rhythm makes a huge difference. And when a sentence felt impossible to rework naturally, I used https://textero.io/paraphrasing-tool/spanish to get a fresh variation and then tweaked it manually. It gave me a good starting point without taking away the original tone. Another trick is to swap in regional expressions you’ve actually heard people use; it keeps the text from feeling like a textbook rewrite.