Hi,
It would help to know exactly which version of W10 you have. You can find out by reading this link:
Find out which version of Windows 10 is installed - gHacks Tech News
I've not seen this behavior on any W10 computers; and I have 10 of them. Just a quick check on the 3 most current W10 versions
(v1511-2015), (v1607-2016), and
(v1703-2017) on 3 different computers does not exhibit this behavior either. I even went into Folder Options in File Explorer and tried to make the folders open on auto-hover; no go.
I suspect no one has the answer, as it's not a normal function in W10; therefore there is no way to turn it off.
I would suspect a virus/malware. Try scanning with whatever AV program you have...