Would it be appropriate for me to email an admissions counselor what the ED acceptance rate is or would this look bad on my part?
It would be bad if the information is on the internet, otherwise, it’s fine.
But remember the ED acceptance rate wil include hooked applicants (ex. recruited athletes, children of large donors etc.)
The ED acceptance rate can be found either on the college’s web page or in the common data set. If you are looking for an acceptance rate to a particular program, you may have to ask, and it is okay to do so.
If by “ admissions counselor” you mean an admissions officer/other at a college/university, the data should certainly be available on their web site. Asking them rather than looking it up yourself probably wouldn’t reflect well. If it’s not (which would be odd), search again and be sure it’s not there. Then it would be fine to ask.
If by “ admissions counselor” you mean someone you are going to pay to help you in the admissions process, data about their success rate is certainly something they should be willing to share.
Although many schools are raising their ED acceptance rates due to Covid, and the most current information is not always available on their websites.