Régis Grison

This plugin is made mainly for french associations, because of the french 1901 law. Feel free to contact me if you think your contry have the same kind of need and I should make some adjustments for it. 
This plugin allow to handle association members by customizing the registration fields to avoid needing an additional listing. It also allows to keep track of the subscriptions. 
Note: This plugin will make use of the ACF (Advanced Custom Fields) plugin and will also contact my server to check for news about add-ons.

Law 1901 association

Handles members of an association and their subscriptions. Mainly for french associations under 1901 law.

wp.insider

smp7

This addon allows you to customize the content protection message that gets output from the membership plugin.
You will be able to specify your custom messages for different types of protection message.
This addon requires the <a href="https://wordpress.org/plugins/simple-membership/" rel="ugc">Simple Membership Plugin</a>.
After you install this addon, go to the “Custom Message” menu from the admin dashboard to use it.
Read <a href="https://simple-membership-plugin.com/simple-membership-custom-messages-addon/" rel="nofollow ugc">Usage Documentation</a>

Simple Membership Custom Messages

Simple Membership Addon to customize various content protection messages.

Law 1901 association vs Simple Membership Custom Messages