I’ve just pushed out a new tutorial video on how to enable note-to-self emails to your vault, locally on macOS, using your existing email account. All you need for that is the built-in macOS Mail app (set up with your email account) as well as my app Actions for Obsidian.
Further explanations and both Shortcuts workflow and AppleScript (as shown in the video) are available at the Actions for Obsidian Knowledge Base.
I hope you’ll like it! If you have questions, just holler. 