5. Why do you need a standalone app to make screenshots? cmd + shift + 5 (or 4) work fine imo.
5. Because I need more functionality.
- Keyboard: cmd+c -> cmd+opt+v
- Non Keyboard: Drag -> Drop
I know that's not the same as right click -> select cut -> right click -> paste, but it doesn't seem strictly worse.
Oh! While dragging a file if you keep the cursor over a directory or over the Back/Forward Finder arrows it will move the focus while move to that dir.
5. I really don't know much about screenshots, their possible functionality or what you are looking for, but this app -> https://shottr.cc/ might serve your needs?