Filesystem driver that enables caching of virtual HDDs for Hyper-V/VMWare/VirtualBox by the host OS
vv
Here is a filesystem driver that intercepts opening of VHD files by Hyper-V/VMWare/Virtualbox and removes the flags that prevent their caching.
It is sold as access to the source files private repository on GitHub, with compiling and signing of the driver left to the user (must be skilled enough how to do that), access being granted for one year.
WARNING: Use with caution and preferaby with a UPS of some sort, because this increases the risk of data corruption. Provided AS IS, without warranties of any kind. Use at your own risk, I am not responsible for any damages it may cause!