In stead of doing it one by one?
there is an API for sharing.
if you share a page with a user all the cards are shared automatically, but i believe domo changed functionality a few years ago so all the datasets aren't shared automatically.
i may be mistaken (@GrantSmith ?) but if you share datasets with a group, all the users would receive access at once. so instead of sharing datasets with users, best practices dictates that we should share with groups to minimize repeated actions.
@jaeW_at_Onyx - Correct. It will share the dataset with all users of that group.
@yli_2596 - You can multi-select datasets in the Data Center and then click the Face with the plus icon in the upper right to share multiple datasets with users or groups.