Org-marginalia-posframe lets you preview the margin notes (Org-marginalia) under point.
(add-to-list 'load-path "<org-marginalia-posframe>")
(require 'org-marginalia-posframe)
Set up your marginalia.org
path, for example:
(setq om/notes-file-path "~/Documents/marginalia.org")
(define-key org-marginalia-mode-map (kbd "C-M-}") #'org-marginalia-next-preview)
(define-key org-marginalia-mode-map (kbd "C-M-{") #'org-marginalia-prev-preview)
M-x org-marginalia-show-posframe
M-x org-marginalia-next-preview
M-x org-marginalia-prev-preview
By clicking the link within the posframe, the window will change to the note location.
C-g
Now, it will open another buffer to edit the note. It would be nicer to edit the note closer to the content.