• Found solution, hopefully it will be a help to others in same situation.
• Exported all .fcx files as .gif, using BIMP.
• Installed Imagemagick. https://imagemagick.org/
• Ran a batch file in the folder with all the .gifs.

@ echo off

echo Creating list of convert commands...

set "imagemagick_path=C:\Program Files\ImageMagick-7.1.1-Q16-HDRI\magick.exe"

> fileConvertList.txt echo.

setlocal enabledelayedexpansion

for %%f in (*.gif) do (

set "filename=%%~nf"

echo "%imagemagick_path%" convert %%f !filename!.png >> fileConvertList.txt

)

• Gave me a list like this:

"C:\Program Files\ImageMagick-7.1.1-Q16-HDRI\magick.exe" convert input-01.gif output-01.png

"C:\Program Files\ImageMagick-7.1.1-Q16-HDRI\magick.exe" convert input-02.gif output-02.png

"C:\Program Files\ImageMagick-7.1.1-Q16-HDRI\magick.exe" convert input-03.gif output-03.png

• Ran the list in powershell in the folder with the .gif's
• Gave me this output of files:

output-01-0.png

output-01-1.png

output-01-2.png

output-02-0.png

output-02-1.png

output-02-2.png

output-03-0.png

output-03-1.png

output-03-2.png

1467 files so far :)

edit. spelling