As long as it's Windows to Windows (or Mac to Mac) then it should simply be a case of putting your CCleaner registration key into CCleaner on the new computer.
If you download and install CCleaner Free you can go to Options>About>Upgrade to Pro
Then simply put your name and key in and then click on Register.
It's similar in Defraggler, start with Help>About on the menu.
I don't have Speccy or Recuva but imagine they will be the same too.
If your licence is for one PC only then you shouldn't use it on more than one, so you need to uninstall the old one first.
If you have any difficulty then you should contact support for help with licensing, it's not something that we can do on the forum other than the basics like above.
You can contact support if needed using this form: <a href="https://support.piriform.com/hc/en-us/requests/new" ipsnoembed="false" rel="external">https://support.piriform.com/hc/en-us/requests/new</a>
If you are changing between Windows and Mac, or vice-versa, then the keys are different formats and so you will need to contact support to get your licence transfered to a new key.