I think it is more of a variation of the Portland Peel or Orange Peel block with the center sharp oval cut smaller (shorter) so that the two squares can be cut from the the ends of the outer pieces.
Example:
https://sewcanshe.com/2015-1-31-clas...free-template/
Possibly using these type of templates in the center of a square block.
Orange peel templates
Perhaps looking at this can help picture it better,
Accuquilt Orange Peel template