The social login plugin will create a regular WordPress user, so there shouldn’t be a problem having Discourse recognize the user. Where you may run into problems is with having the wp-discourse plugin recognize that the user’s email address has been verified by the social login provider. Will you have other login methods available on your WordPress site, or will it be limited to logging in with a social login plugin?
This is referring to the WP Discourse plugin. For details about disabling the Discourse activation email with the WP Discourse plugin, see this topic: How to Deactivate the Discourse Activation Email