WordPress User Registration with Only Email Address

In previous tutorials, we learned how to create WordPress registration forms without requiring users to enter their username and password. Do you know you can also create a custom WordPress registration form with just an email field? where users can register or sign up to your WordPress site with only their email address without a username, password or any other custom field values. This is exactly what we’ll be building in this tutorial.
If you want to jump ahead of the tutorial below, you can view a demo of the email only registration form here and download the form theme here. We have a guide on installing ProfilePress form themes here.
Building the Registration Form
I assume you have ProfilePress installed and activated. If not, do that now.
Navigate to ProfilePress >> Registration Form and click the “Add New” button.
Add the code below to Registration Design.
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Create an Account in Seconds

[reg-email title=”Email Address” placeholder=”Email Address”] [reg-submit value=”Register”]

And the CSS for
Source: https://managewp.org/articles/14758/wordpress-user-registration-with-only-email-address

source https://williechiu40.wordpress.com/2017/04/03/wordpress-user-registration-with-only-email-address/