I like to know if there is a way to change the picture with name initials on email body.
You can change the settings in Menu > Tools > Settings > Contacts > Avatars.
eM Client will first check to see if you have a Contact for that email address that has a picture. If you do, it will use that picture. If you don’t have a contact picture, and you have selected to download avatars from external sources, eM Client will attempt to find a registered avatar for that address. This can come from sources like Gravatar or Google + profiles among others. If none can be found, then it will use a monogram (as in your screenshot). If you have not selected to show monograms, you will get a generic silhouette.