One thing more annoying that reading someone's horrible handwriting is having to install a custom font just to read an email. I honestly do not know whether the security setting on my work machine even allows for custom/bespoke fonts in email. It has never come up before.
Sites like [calligraphr](https://www.calligraphr.com/en/) can help you create fonts from your handwriting. Also, here's an old project for creating something that looks handwritten on paper.