Acorn is one of the two best1 Mac image editors for normal humans. Retrobatch, from the same developer, is a batch-processor for images, letting you build simple or fancy workflows that can do pretty much anything to your images, automatically. If you regularly resize photos, remove location data, add watermarks, or anything else, this is for you.
Even crazier is Retrobatch’s machine-learning component, which can apply filters and operations based on what it sees in the image. For instance, you could drop a folder of images onto Retrobatch, and it would check them all and only apply filters to pictures of hot dogs. That’s right. It can detect pictures of hot dogs.