You may want to try @Grum999’s plugin Buli Commander, which I like very much.
It is a fully fledged file manager for Krita that can preview all image formats Krita can handle, you can set different sizes as well as different ways to how they are presented.
The version linked in the plugins opening post does not work anymore, but it is said that the below linked patched version runs also on the 5.3.x versions of Krita.
The plugins full description and manual is found here.
Alternatively, you may want to try @EyeOdins ImagineBoard which also allows browsing and watching files, although the main purpose is a different one, it may be the plugin you prefer, its wiki is found here.
Michelist