To convert one virtual machine from one format to another, you will need all the relevant files not just few. So just simple HDD to PVS conversion is not possible, while as whole you might be able to convert the virtual machine using Parallels Desktop.
Convert Parallels Desktop or Workstation virtual hard disk to Parallels configuration data.
We have found 3 software records in our database eligible for .hdd to .pvs file format conversion.
Microsoft Windows software - convert hdd to pvs on Windows
A virtualizing solution for small businesses and professionals
Convert from hdd file format
The tables with software actions are a good pointer for what a certain program does with various file types and often may give users a good hint how to perform certain file conversion, for example the above-mentioned hdd to pvs. However, it is not perfect and sometimes can show results which are not really usable because of how certain programs work with files and the possible conversion is thus actually not possible at all.
Apple macOS / Mac OS X software - convert hdd to pvs on OS X
Mac version of the popular virtualization software
Linux/Unix software - convert hdd to pvs on Linux
Virtualizing software for Linux operating system.