Wow! I would take several scrap pieces and cut and play with them before I began this project.
I don't know if this is correct or not.
Calculating 2" finished square:
4.078" square cut twice on the diagonal for side setting triangles. I think you would round up to 4 1/16" or 4 1/8".
2.29" square cut on the diagonal for corners. I think this would round to 2 3/8".
Help! Does this sound correct?