There is no straightforward way to moderate user accounts because User entities are not revisionable. There is also no easy way to make them revisionable.
Instead, you will have to create your own solution. Core provides some tools to make this easier.
For example, if you want to create a social media site with user profiles that are subject to moderation, do NOT add the fields to be moderated to the user entity. Instead, create a node content type (such as "User Profile") and add the fields there. Make those fields subject to moderation.
You will need to implement a lot of other things as well-- you may want to automatically create a "User Profile" when a user account is created, and you probably want to prevent the user from creating more than one "User Profile" entity.