Bookmarks can be backed up and restored to your other devices using iCloud. Firstly, make sure you have turned on iCloud support in Settings in all your devices you wish to share bookmarks.
Firstly, tap the Bookmark icon on the tab bar to show your saved bookmarks and any custom folders. These bookmarks will be copied to another device using this method.
Tap the Export icon on the bottom-right of the left panel.
Select iCloud Backup.
Then on another device that uses the same iCloud account, go to Bookmarks and tap on the export icon again but choose iCloud Restore.
All bookmarked words - with any custom memos - will be automatically inserted into subsequent devices.