An ongoing frustration with the iPad photo workflow is that everything must pass through the Photos app. If you use another app such as Lightroom CC for iPad or iPhone, you end up with duplicates of everything: the copies of your images in Lightroom, plus the ones that were originally imported into Photos.
A recent update to Lightroom on iOS added compatibility with Shortcuts, Apple’s architecture for automating all sorts of things. In this video, Brian Matiash shows you how to configure a shortcut that takes the previous import into the Photos app, imports those images into Lightroom, and then deletes them from Photos.