I’m thinking of a dozen different atlases each with a graphic you want, and a level that only wants one graphic from each of those atlases. Is it possible at the start of the level to create one new texture atlas with only the sprites/textures you want?
The answer here is ‘yes’, although I don’t know about performance yet. Use Texture2D.GetPixels() to read from a texture and Texture2D.SetPixels() to write them. Another major issue is that the textures must be uncompressed. My current thinking is to save the images as .pngs in Resources and load/copy from there.