Thanks for your reply, @konstantyn_diachenko
Our AEM instance is on-premise, so we don't use Web-Optimized Image Delivery available in the AEMaaCS.
The images do not have an imageFlipHorizontal as part of their properties.
We do allow authors to make edits to images using options available in the cq:inplaceEditing node as part of our image component policy that is set in cq:editConfig. One of the options is the flip option. We also have this as part of our cq:design_dialog.
- components/content/image/cq:editConfig/cq:inplaceEditing/plugins/flip
- components/content/image/cq:design_dialog/content/items/tabs/items/features/items/content/items/accordion/items/orientation/items/flip
That being said, an author/editor has to choose to flip an image, so these shouldn't cause the auto-flipping we are encountering. I did test removing this plugin just to be sure, and it did not eliminate the problem.