Sasori wins this mid diff,,
-Sasori starting in hiruko immediately allows him to counter genjutsu perfectly since he would be hiding under hiruko jus fine,,,
-Danzo does not have the speed and evasion feats to evade everything that sasori uses at him,, as through this sasori can defeinitely land good poison hits on danzo,,
-Sasori also has the third kazekage IS which has a large enough AOE to make as well as attack range and usage to force danzo to use his izanagi,,
-Sasoris hundred pupppets are too much for danzo as their diversions and constant attacks will make danzo run out of his izanagi reserves,, thus giving sasori the win,,,,
-Not to mention having no intel about sasoris weakness,, as well as the latter being a puppet himself,, is also why sasori would win this,,,considering that KA is not included