To troubleshoot Slow Right-Click Context Menu in Windows we need to edit the context menu. Most of the time the problem is caused by some items on the context menu.
Or maybe you have too much items on your context menu. In both cases the following solution will work.
Please BACKUP YOUR REGISTRY BEFORE CONTINUING ON in case somethings goes wrong.

Go to HKEY_CLASSES_ROOT\Directory\Background\shellex\ContextMenuHandlers

Delete everything just leave Folders NEW and Workfolders,
This is easy way to fix slow right click in windows 10/ 8.