In order to share map data, you will need to be a user on both accounts with at least the “Edit Locations” permission. Once you are both accounts, you will go to the Map Data tab within the account you want to share the data from and there should be a “Share Map Data” button. You will select this and choose which departments you want to share with. If this is not showing, please make sure you have been added under both accounts with the same email address.