If you cannot pay, consider fully open-source downloaders that have no paid tier. These are safe and portable in many cases:
JDownloader 2 (graphical interface, open-source)
4K Video Downloader (free tier with limitations; paid version but no cracks needed)
Using a cracked license key violates the software's EULA (End User License Agreement). While individual users are rarely sued, there are other legal risks:
Downloading a "Video DownloadHelper license key portable" from an unofficial source exposes you to severe risks. These are not theoretical—they are well-documented by cybersecurity researchers.
Users want the premium features without paying. This leads them to search for: