Moving edited files in Lightroom classic from one folder to another folder.

By Lightroom CC, do you mean Lightroom Classic? I think that message appears in Lightroom Classic only.

The message is confusing. To understand it, it’s necessary to separate the notions of the History panel and the Undo stack. The message is warning that a folder move is not something Lightroom can undo, and also gets in the way of the older Undo steps. What that means, exactly, is that if you move a file to a different folder, you can't use the Undo command to back up before the move.

BUT…that is not the same as losing the Develop module edit history of the image. This is the confusing part, and why it’s important to understand the Undo stack as slightly different than the Develop history. If you move a file to a different folder inside Lightroom Classic, that does not wipe out the Develop history. After a move, you will see that the History panel still contains all of the edit steps for that image. The database inside Lightroom Classic keeps all image metadata associated with the file, until the file is deleted.

Another way to understand this:

• The History panel list of edits records the changes made in the Develop module. Except for a few other actions like exporting or printing, the History panel does not record changes made outside the Develop module.
• The Undo command records steps made in all modules, like applying keywords and changing sources.

That difference is the key to understanding that confusing message. If you move a file between folders inside Lightroom:

• Yes, the complete list of Develop module steps in the History panel is preserved for the file you moved.
• No, you cannot use Undo to back out of the move or previous changes. After a move, if you want to undo a recent change you made to that image, you will have to select that earlier step in the History panel.

You will not lose the ability to undo edits, except you can't use the undo menu for it. Instead you simply have to change the edits in the develop module to what you had used previously. Lightroom is a non-destructive editor, so there is no difference between using 'undo', or history, or simply setting back sliders manually.

All your edits and metadata will stay with the photo.  The "unclear" dialog just means that the UNDO stack is cleared and you will not be able to do any undos after the move