Save File Modification in Retroarch

Hey there,

I have recently been playing Final Fantasy VII on my New 3DS XL and found a 100% complete save file online in “.mcr“ format. I wanted to replace/overwrite my current save file in Retroarch (PCSX-ReARMed Core) which is in “.srm” format but don’t know how. Also, I’ve tried going into the “savefiles” folder in the directory “sdmc:/retroarch/cores/savefiles/FF7.srm”, renaming my “.mcr” save file, and overwriting my current save with the newly renamed one, but when I go to boot up the game, there’s no save registered on either memcard1 or 2. Could someone please guide me through this? Thanks in advance!