I journal pretty much every day and just finished hand porting all of my entries to One Note. It did require downloading all of the images used and then inserting them into Joplin. I also found that Emojis don’t convert over.
Something that I found though: when you copy and paste any image from OneNote to Joplin, if there’s any text in the image (even on signs for shops), Joplin will convert that to plain text without displaying the image itself. Instead, it will show that text and some garbage code in random locations.