You will rarely find a stable free link. Any link claiming to have "all Sky channels" free is likely a honeypot or will die in minutes.
The following papers provide comprehensive insights into the ecosystem: 1. Investigating IPTV Malware in the Wild (2023/2026)
Look for legal IPTV services with free trials (many offer 24–48 hours) or low-cost legitimate providers ($5–15/month) that provide stable M3U/Xtream codes.
