Gutenberg gallery

Hi I don’t know if this is the right forum to ask.

I have been using wordpress for years with jetpack tiled galleries. I have them in hundreds of posts. Now I want to cancel the jetpack plugin and convert the tiled galleries to standard guttenberg galleries due to speed and amount of unnecessary code. One at a time it’s not a problem but it’s over 500 posts. Does anyone know of a fix or plugin that would allow me to do this reversible conversion in bulk?

Additionally I would need this with media conversion from NONE to LINKTOFILE

Thanks for any idea

The page I need help with: [log in to see the link]