Yeah you can. Use Word or some other text writer. Type something in the font you want and then copy and paste into your sticky note. Then when you delete that the font stays changed.
The only drawback is that after you delete that note it goes back to the default font. You can use the Taskbar icon to close the window and when you turn it back on it will have the same note. If you keep recycling the same note you'll keep your font.
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