No, it will not be overstocked. I am assuming live plants, even if just floating. And weekly water changes of 50-70%. Nine cories, 12 danios, 9 pencilfish and 9 hatchetfish, just so we are on the same page. If you do the gourami instead of the pencils and hatchets, fiv e of those, and I would look for another upper fish, I'n just leery of combining gourami and other surface fish. Another rasbora that does work with the gourami and the danios is Trigonostigma hengeli, the smallest of the three "Harlequin" rasbora. This fish remains mid-tank, and I have had them in with pygmy gouramis with no issues. A group of 11-12 of these rasboras, with the gourami (5), danios (12) and cories (9).
None of the above is anywhere near close to overstocking. Fish that are compatible, and in decent numbers, have less impact on the biological system than fish that are not.