Is there a name for embroidery that is only an outline?
Redwork Embroidery - also known as blackwork or Baltimore redwork/blackwork. Color relates to the thread. Simple backstitch outline work.
Back in the early 2000’s it re-emerged becoming a popular and fun craft. I met the folks from Sublime Stitching at the ArtStar Craft Festival and got the sexy librarian kit seen in the pic below. You can still buy iron-on pattern kits with lots of interesting outline patterns.
Here is a link to a website that explains the history with citations:
http://www.womenfolk.com/quilting_history/redwork.htm
I do not have any direct association, I just knew to look up Baltimore Redwork from reading American Quilter magazine.