Unfortunately that was not possible to achieve this regarding this 2 question.

But what do you think if you consider to use back Easysocial on your site?

The reason why i suggested this is because Easysocial has the migrator for migrate Community builder user data over to Easysocial.

And you can able to set ACYMailing custom field from the Easysocial profile type, so this field will appear from the user edit profile page, user can through this way to subscribe it.

And you can able to set integration with Easysocial user profile from Easydiscuss setting.

Thanks Arlex, yes, EasySocial is very interesting because it is feature rich, but it has a lot of features I don't need, like streams, events, pages, etc. And I guess it could overload my site without a real necessity. So I am trying to keep my site with the lower number of extensions and plugins as possible. I just need a user profile better than core Joomla user, and not a large community like EasySocial.

Do you understand me?

You're welcome.

I understood, thanks for took your time to explained this.