VirusTotal scans of popular "Movavi patches" show:
Movavi has never released a legitimate patch to convert trial to premium. Any file claiming to be a "patch" for version 19.3.0 comes from third-party hackers. Movavi Video Converter 19.3.0 Premium Patch
Using a patch violates copyright law. While individual users rarely face lawsuits, you could receive DMCA notices from your ISP. Businesses face fines up to $150,000 per pirated copy under U.S. law. VirusTotal scans of popular "Movavi patches" show: Movavi