Solved: Newbie Question: How to pass a variable (foldername with spaces) to a Third Party Plugin

Found it...

https://forum.keyboardmaestro.com/t/copy-folder-between-devices-and-add-date-time-stamp/

Then you have typed the wrong quotes manually, I guess. In general, when writing scripts/code you always use straight, typewriter quotes ('', ""), never the quotes you use in prose (‘’, “”).