When you are purchasing any additional salesforce licenses like Apex Interactive Debugger, Feature License – first enabled in production org based on your special request same license will be enabled to your sandbox(not all sandbox) or will copy over from next sandbox refresh.
Salesforce have option to sync production licenses to any of your sandbox using “Match Production Licenses” button. Once you clicked that button – it will sync licenses and send you an email once completed.
Where to see “Match Production Licenses” button?
Go to Setup –> Type “Company Profile” in Quick Find search text box –> Click “Company Profile” menu
–> now you can see “Match Production Licenses” button.
–> Click “Match Production Licenses” button. you will get pop up.