Pages on main site - User with account can only join another site by admin action

[alexrollin]

Network Activation - pages on main site
After registering as a subscriber on a subsite1, user is now listed in network users.

However, user cannot join a different site (subsite2, subsite3)through their own effort.

1. Try to register on another site: username and email exist
2. Try to login on subsite2: redirected to WP Backend profile on subsite1

The only way to add the user to subsite2 is if admin add the user to the site.

[wpdev10]

Need inputs from @Stiofan

[alexrollin]

@Stiofan @wpdev10 - users need an admin action to become members of other sites? Yes No?