Sorry to hear that.
Steinberg Plugin User Presets
So here’s some good news. You should be able to retrieve most of your Steinberg stock plugin user presets from your old computer by simply copying this folder:
C:\Users\Username\Documents\VST3 Presets\Steinberg Media Technologies
This folder contains all your user presets which are related to Steinberg plugins. After copying the old one you should rename the folder on your new system temporarily as “_Steinberg Media Technologies” before you insert the old one. It shouldn’t be necessary but it’s always better to be safe than sorry. This simple trick should revive all Amp Rack and Reverb presets and most other stock plugin user presets.
Waves
Did you save your Wave plugin preset as vstpresets? This happens automatically whenever you save a preset here:
In this case all your user presets reside here:
C:\Users\Username\Documents\VST3 Presets\Waves"Plugin-Name"
Otherwise, you’ll find them here:
C:\Users\Public\Waves Audio\Plug-In Settings"Plugin-Name" User Presets
Cubase
I assume you also had customized key commands, settings etc on your old system. Why you are at it do yourself a favour and create a Profile . You can copy that profile (make sure to read the instructions in the link first) and you should have almost everything on your new computer just by copying and activating that profile.
All in all it’s just two folders and one profile file in your case if you are just looking for these presets.
Backup & Restore function
The Backup & Restore function that @fese mentioned above is compatible from Cubase 12 upwards. This is the most elegant way to do all that stuff and much more. Definetly worth looking into!
Since it’s only two or three files you can do it manually, too, of course, like I described above.