How I was able to port Outlook Notes over to Mac Notes app. I am using the 365 version of Outlook on the Mac. As Microsoft is discontinuing Notes I found many posts inquiring how to move off the Outlook app to Mac Notes, but I did not see answers how to port all at once only one at a time. If you are prompted to use the trial version of Outlook, do not, or if you have turn it off with the switch in the upper right corner as Notes are eliminated, better stated--not seen.
Step 1: Create an empty folder, I chose the Desktop.
Step 2: In Outlook with Notes selected and all in view select all (Command A)
Step 3: With all selected - File --> Save As
Step 4: Navigate to the folder where you want to create the files and Click Choose
Step 5: Open the Notes app - File --> Import to Notes...
Step 6: Select the folder where the files were written. Note these are html files, not to worry.
Step 7: Click -- Import -- a prompt will appear indicating it will import to a folder labeled Imported Notes -- Click Import Notes.
You are now free to select and move them to the Notes folder or wherever you wish.
Michael