How to Force Admin Approval of New Users?
This Article used to recommend the New User Approve plugin. Though it does still work, we now recommend a new 3rd party add-on shown below and found here. The 3rd party add-on was designed specifically for MemberPress and provides more flexibility.
Though MemberPress itself does not currently have a Member approval system in place, there is a new 3rd party add-on which handles it quite nicely.