Guust

The user already can have a tab to their listings, so a visitor can follow those links to see the reviews for each listing. If you would add all the reviews in one tab, then how are they useful for the visitor if the user has more than one listing?

I also asked a developer to look at your question.

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Sites on a multi-site always share users.
You cannot register a user with the same username on different sites.
If a user is registered, he/she can be given access to different sites or not, see Network Admin > Sites > Edit one of your sites > Users tab.

See also
https://userswp.io/docs/network-activation/
https://codex.wordpress.org/Multisite_Network_Administration

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Your users are not registering on WordPress, that WP bar is standard on many themes.
You can contact the theme developer to ask how to hide it for non-admins, or have a look at articles like https://www.wpbeginner.com/wp-tutorials/how-to-disable-wordpress-admin-bar-for-all-users-except-administrators/ for help.

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Your browser is remembering the earlier login, so you will have to delete the remembered credentials or delete your cookies.

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Something wrong there …
Can you post your URL and Wp admin details in a private reply please, and also the URL of that page you show in the screenshot.

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You can turn off the options if you do not want any social aspect of your site, and just use the parts you like.
I’ll get the developers to have a look too to see if there is some simple code to hide the profile page from other users.

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Please give us a link to “the previous post”.
And add your URL and WP admin details in a private reply so we can check.
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