You cannot directly sync Workspaces with tabs using Opera Sync, so a manual migration is required. The process has two key parts:
Backup Tabs: Manually save all open tabs within each Workspace to a uniquely named Speed Dial folder. Then, export all Bookmarks (which includes these folders) to an HTML file.
Migrate Profile: Copy the entire Opera Profile folder (found via opera://about) from the old PC to the corresponding location on the new Windows 11/Parallels installation.
After migration, your Workspace names and settings should appear, and you can re-import the HTML file to the new browser, allowing you to open the saved tabs into the correct Workspaces.