Yes, Portfolio Manager users can share properties and meters in bulk with web service providers.
Bulk sharing with a web service provider that does not require property or meter-level custom fields can be completed from within Portfolio Manager. First, click Set Up Web Services/Data Exchange on the Sharing tab (first screenshot), then specify the account you'd like to share with, the properties you'd like to share, and the permissions you'd like to set for those shares. Then click Authorize Exchange (second screenshot). Portfolio Manager will then alert you to any issues with the shares you've submitted.
If you're sharing a large portfolio with a web services provider account that does require custom fields, when you click Authorize Exchange Portfolio Manager will provide you with a downloadable Excel template that you'll need to populate with data including the properties and meters to be shared, the permissions levels you'd like to set for each one, and the necessary custom field information (third screenshot). You can send the completed template to the Portfolio Manager technical team here to complete the process (fourth screenshot).