Running a 20-year-old VST in modern digital audio workstations (DAWs) like FL Studio or Cubase presents several hurdles: How can I obtain a Steinberg Hypersonic 2 Licence? - HALion
eBay, Reverb, or KVR Marketplace sometimes sell used Hypersonic 2 licenses complete with the USB dongle. Prices range from $50–$150. If you buy that, you get the original installer. Steinberg stopped supporting license transfers for Hypersonic, but the dongle authorizes offline anyway. hypersonic 2 setup.exe download
and select "Run as Administrator" to ensure the installer can write to the VST plugins folder. Compatibility Mode Running a 20-year-old VST in modern digital audio
If you bought Hypersonic 2 back in the day and still have: hypersonic 2 setup.exe download