I am working on intelligent feedback currently. I am seeking for help. I am sure about the strategies for giving feedback but not sure about how to do it.
I DON'T recommend Grammarly, as engaging with it seems to activate pop-ups for less savory services i.e. paper mills, ghostwriters, and specifically targets ELLs to procure these, potentially getting themselves kicked out of school in the process. Much more useful as a GUIDELINE, not the God, is Turnitin.com's ESL proofreading tool that instructors can turn on when checking for similarities. You can use the pre-built, and you can add/delete custom symbols. https://turnitin.com/static/resources/documentation/turnitin/sales/Turnitin_RELEASE_080311_ETS_erater.pdf It has a check-box for ESL. Bonus: Even if the advice does not apply, it opens the conversation with the student on that specific issue. Hope this is helpful.