If you self host both Lemmy and Ntfy, you can enable Ntfy's SMTP receiver, and have Lemmy send emails to that port. It's not well formatted for Ntfy but it works. Anything Lemmy would have sent an email for will be sent to Ntfy, and Lemmy thinks it's sending an email.
I just got this set up for myself and it works pretty well! You just need to use a specifically crafted email address with a token in order for it to work.
However, this is only really viable for single-user instances. For myself, this is the perfect solution. But for others with more Lemmy users, unless you want to be manually managing tokens for all of your users, this is not a good solution.
If you don't self host Lemmy, I guess you could still self host Ntfy as an open email server and get them that way, but that sounds like it could get messy.
