I altered the Images as Planes import script to auto set the Blend Mode of imported images with Alpha to Alpha Blend. This way you can see through them in the viewport, after they load.
Add two lines to the import script (io_import_images_as_planes.py) around line #1007. Inside function create_cycles_material
material.use_nodes = True if self.use_transparency: material.blend_method = 'BLEND'
version: 2.80 (sub 74), branch: blender2.7, commit date: 2019-06-09 21:43, hash: 030c7df19da9, type: Release
build date: 09/06/2019, 17:18