ubuntu – data size difference windows linux

This might be a seemingly noob question, although I’ve been searching for an answer and still haven’t found it.
My problem is that I get a pretty big difference in data size checking the same drive on Windows 10 and Ubuntu 20.04.
I know that most (if not all) Linux distros manage folders as files, therefore a given folder’s size may appear bigger than it would on Windows. But this should only work comparing the different sizes that same folder on different file systems.
Although I get the same result checking the same, NTFS formatted external hard drive on these OSes.

Thanks in advance for your help