How to send automatically new question email notification for all registered user without set emails?

Question

I need a plugin or solution for -

1. Automatically send new question notification to all registered users.

2. I don't want to set emails one by one separate by comma etc. I need all users directly from the database .

3. If someone posts a new question then new question notification should be sent to all registered account.

Comments

I also need this

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You shouldn't do this without having an unsubscribe option or else the mail server might be reported as spam.

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Any plugin with an unsubsribe option?