I made a simple import plugin for importing ZIP archives as textures. Thought I’d share.
More specifically, it can load multiple images from a ZIP archive, and import them as one channel-packed texture. This allows you to maintain your metal, roughness and occlusion maps as separate images, but still load them as one texture with no extra work.
All image formats that Godot can natively handle are supported. Channels can also be inverted, allowing you to load a gloss map as a roughness map, or flip the y channel of normal maps. Several importer presets are available for common use-cases, such as importing albedo, normal, ORM and emission textures.