Large fur muffs were popular in both the very late 18th C and early Regency and then again in the Edwardian. So making on is a good multi-purpose costume accessory. AT the bottom of the page there is a downloadable pattern with instructions.
An example of an Edwardian muff from the pages of Eaton’s 1913-14 catalogue, Eaton was Canada’s main mail order catalogue similar to Sears and Roebuck in the US.
The lady on the left has her over size muff behind her, the fur matches her hat and the edging on her wool outfit. 1915
Laurie Tavan is modeling a muff made from this pattern with some vintage Faux Shearling which I also used for the hat. The coat has a similar but longer pile modern faux Shearling.
1787 period cartoon showing an exaggeration of a large muff.
Alex Adrian is modeling a white Fox fur muff made from this pattern. Her dress was made by Katherine Adrian, her Spencer and hat by Lynn McMasters. Laurie Tavan is on her right and her outfit was made by Deborah Borlase and her hat by me.
It looks like the pattern above was missing pages 21-25 which cut off the muff pocket pattern I have replaced it with this pattern piece. I also added an illustration that shows the placement of the pocket on the Muff lining.