Because this is a modified, unofficial version of Windows, it is not available through official Microsoft channels. You can typically find it on archival sites: Internet Archive
– This is not a Microsoft release. “Sweet XP” is a custom, third-party “Windows XP modification” (often called a “Windows mod” or “custom XP build”). These are created by individuals, not Microsoft, and often include cracked software, tweaks, or themes. Windows XP Sweet 6.2 Final Francais ISO