What would you use instead of Photoshop on Linux Mint?

I’d split the work rather than hunt for one perfect replacement. Darktable is geared toward RAW photos and non-destructive adjustments, while GIMP is useful for layer-based edits and general image work. Hugin is another option specifically for stitching panoramas. Those are separate tools to learn, but each fits a different part of your list.

For the straightforward tasks, check what your image viewer offers before installing a big editor. Gwenview has basic image tools such as rotation and resizing. For panorama stitching, Hugin is worth a look, though its interface may take some getting used to.

GIMP is probably the closest general-purpose starting point among these suggestions. It can handle lots of ordinary editing, but it won’t feel exactly like Photoshop, so expect to learn where its tools and terminology live. For RAW-focused, non-destructive adjustments, pair it with Darktable or RawTherapee rather than expecting GIMP alone to cover every workflow.

Since you work with both RAW and JPEG files, I’d try Darktable for the photo-development side and see whether its workflow clicks. It’s aimed more at managing and adjusting photographs than at being a direct Photoshop clone. GIMP can fill in when you need a more general image editor.

One suggestion was Affinity, but it isn’t a native Linux application, so it may not suit your goal of a straightforward Mint setup. I’d start with Linux-native options such as GIMP, Darktable, RawTherapee, and Hugin, then test the specific tasks you rely on most.