Flameshot - Powerful yet simple to use screenshot software for Linux.
Nimbus Screenshot - Take screenshots and record video from your screen
Gnome Screenshot - GNOME Screenshot is a utility used in the GNOME desktop environment for taking screenshots.
Greenshot - Greenshot is a free and open source screenshot tool that allows annotation and highlighting using the built-in image editor.
ShareX - ShareX is a free and open source program that lets you capture or record any area of your screen...
Snagit - Screen Capture Software for Windows and Mac