I'm pretty sure most non-native speakers (one here) do the same. I'm not talking about three-paragraph-long Slack thread, but even a single message where I feel otherwise unable to convey what I need _the way_ I want.

You don't need a fake extended vocabulary. Just communicate directly and honestly. Underlining spelling errors as you type has been a standard feature of email software for nearly three decades.

> I often send out the LLM version, but still check if it contains the original thoughts correctly.

Please don’t do this. You probably aren’t aware of how bad this can land. It’s not just about containing your original thoughts, it’s about the verbosity, repetitiveness, and absurdity of it all.

Grammarly is a much better tool for these kinds of purposes, and it actually guides and teaches you to improve your writing along the way.