I had my computer in Norwegian language and it caused the path you have to choose to be wrong when I copied it over.
I copied my windows path to git and it automaticly converts the my program files to the english naming. But what I really needed was my localized name which was 'Program Filer' instead of 'Program Files'.
To test this issue switch your computer language over to something else and try to copy the git path over into the plugin path text field.
I had my computer in Norwegian language and it caused the path you have to choose to be wrong when I copied it over.
I copied my windows path to git and it automaticly converts the my program files to the english naming. But what I really needed was my localized name which was 'Program Filer' instead of 'Program Files'.
To test this issue switch your computer language over to something else and try to copy the git path over into the plugin path text field.
EDIT: This is UE 4.27.2