Save Conversion Issue with Desmume Core

When converting my .sav from supercard dstwo to .dsv for desmume core, i get corrupted saves for some games. ive tried every converter and all have the same results. Is the core not blocking antipiracy coding? what’s going on? FFIV and 4 heroes of light work but chocobo, FF12-2, and mana games have a save data corrupted message. Help! Can someone just code in that desmume just uses .savs?