I always use Grammarly too. I've tried using Hemmingway, but I'm not able to write that concise.

Btw, none of those AI checkers are reliable. Many have false positives and they can also be bypassed with a few edits. I don't know how they are able to offer such a misleading and useless product without getting sued.

The main thing for Medium is to include a disclaimer if you use AI to write an entire article. I know most people don't include it, but it's easy to notice AI writing most of the time.