GIMP

Languages: English (once downloaded, the software provides interface in different languages).

GIMP is a cross-platform image editor available for GNU/Linux, macOS, Windows and more operating systems. GIMP provides the tools needed for high quality image manipulation. GIMP is used for producing icons, graphical design elements, and art for user interface components and mockups.

It is free software, you can change its source code and distribute your changes.