Per https://1password.community/discussion/comment/602837/#Comment_602837 , people have been asking for this for a long time, but there's still no way to do this without carefully re-creating sections in order. That would be needlessly high-stakes, though, since a mistake could cost you the ability to log in (at least, without careful debugging of your vault history & backups).
I really hope this improvement is coming soon! :-) I'm very surprised (and dissapointed) to see this feature request missing after so many different calls for it to be implemented. Here are just a small handful of the threads I found, I see some dating as far back as 6 years ago:
Per https://1password.community/discussion/comment/602837/#Comment_602837 , people have been asking for this for a long time, but there's still no way to do this without carefully re-creating sections in order. That would be needlessly high-stakes, though, since a mistake could cost you the ability to log in (at least, without careful debugging of your vault history & backups).