How can I implement single sign-on between 2 WordPress sites?

I have a main site, let's call it mysite.com. This is a WooCommerce site with lots of users.

I also have a multisite network mynetwork.com. My main user account at mysite.com is duplicated at mynetwork.com.

I want to be be able to sign in with my account at mysite.com and also be automatically logged in to mynetwork.com. Is there a plugin or other technique that would allow me to enable this? Thanks