remove unneeded files

We're moving to a new version for out software, for that version I copied the entire projectsuite folder and renamed it.

(Basically creating a new projectsuite in the process).

Now when I'm looking through all the files within that folder I see so many files that are unused or copies of other projectfiles.

I want to clean up this folder without removing necessary files. is there any way to see what files aren't used without trail and error?

as an example within 1 project folder inside the suite folder:

it seems like most of these are unneeded

EDIT: this also counts for keywordtests, I've found a few that have been removed from the projects but are still in the files