qimgv is described as 'Qt5 image viewer with optional video support. Ability to quickly copy / move images to different folders. Can open some extra formats (JPEG-XL, AVIF, APNG, HEIF/HEIC, RAW) via third-party image plugins' and is a Image Viewer in the file management category. There are more than 100 alternatives to qimgv for a variety of platforms, including Windows, Mac, Linux, Flathub and Flatpak apps. The best qimgv alternative is IrfanView. It's not free, so if you're looking for a free alternative, you could try IrfanView or XnView MP. Other great apps like qimgv are ImageGlass, FastStone Image Viewer, XnView Classic and qView.
I like the option to see all files inside the folders in the current directory. I like the controls, the ability to watch videos. It's the best secondary viewer to my primary qimgv