WordPress support shows Gravatar by default, because Gravatar is by remote call, the loading speed is sometimes affected, in addition, the application of Gravatar is a litted difficult. For the wordpress website, It is necessary to allow users to customize the avatar in the profile page. WORDPRESS BEST PLUGIN recommended two plugins which support registered users to upload their photos.
WP User Avatar
After installing WP User Avatar, you can upload your own avatar in the backend – settings – discussion, also you can set the default avatar in the backend – users – my profile. As a result, if the user set their own photo in the “profile”, it is preferred to display, if not set, it shows the user’s Gravatar picture, or the site’s default avatar.
Simple local avatars
Simple local avatars support to upload the local photo as the profile avatar for a registered user, if the user upload a custom avatar, will not call remote Gravatar, but call the local custom avatar; if the user does not uploaded custom avatar, then call his Gravatar or Gravatar default avatar. Custom avatar first!