I’m using the latest version of DTP Office. I can find no way to indent text in a formatted note. But when I copy indented text into a formatted note, the indentation is preserved. Am I missing something?
No, this is not yet possible.
But it will be possible someday?
Maybe. At least in the near future there are more urgent tasks, I’m afraid.
Hello, I was looking for this function, too. And I found this topic today.
I imported many notes from Evernote with import function of DEVONthink to change note-taking app from Evernote to DEVONthink Pro.
Most of them contain lists, but they are imported as formatted notes automatically, so I cannot edit them as I want.
List structures are kept and de-indent is easy (just press return key), but I cannot add indent.
What is the best (easiest) way to solve this situation?
(if you have good workaround, please tell me. But ideally, I want you to add indent function. It should be easy because de-indent is already available.)
Never assume something is “easy”. It’s better to assume it’s not and be told it is. 
One workaround might be to convert the notes to rich text but in case of web clippings this isn’t recommended due to the poor layout.