Processing the tags in names in the JSON from Affinity is an interesting idea. One problem is that Spine doesn't manipulate your image files. It could but doesn't because it can be surprising and is better managed elsewhere. If the images have tags in the names, you'd probably want them renamed. We'd need to make it clear in the import UI that this will happen.
Another solution could be to export full frame images for each layer, then we could provide a tool that trims whitespace and imports into Spine. This would mean we'd no longer need scripts for each image editor, as long as they can write out a full frame image for each layer. One problem is that the draw order is lost. We could bring the images into Spine in the right positions, but we wouldn't know which images are on top of others. Using the file's creation date probably wouldn't help, as I'm not sure it's granular enough.
Update: We've reached out to the Affinity Designer guys and they are willing to add built-in support for tags! It's really great they are so responsive. 🙂
