WhatsApp currently offers three options for displaying your last visit status, profile picture, and information about you. The messenger allows you to make them visible to all users who have your phone number, hide them from all users, or make them visible only to users from your contact list.
Thus, if you want to hide the time of the last visit from certain contacts, you have the option to hide it only from everyone, or limit the visibility only to your contacts and remove those extra “certain” contacts from your phone. But that may change soon.
WhatsApp is reportedly working on a new visibility option that will allow you to hide your last visit status, profile pictures, and information about you from certain contacts. According to the source, the messenger is currently testing a new option “My contacts except”, which will allow you to specify which contacts you want to hide your data from.
At the moment, the new option is not available in the current beta version of WhatsApp. But it should appear in beta versions of WhatsApp for iOS and Android soon.