i tryd the paint.net, it was quite easy, but kia forgot that u have to switch back to the "Move selected pixels" tool.
and u mist some steps,
- Open the image.
- select the "ellipse select" or "rectangel select".
- select the part u want to rotate.
- select the "Move selected pixels" tool
- turn the quality to "pixelated"
- Right click the image.
- Drag to 45 degrees.
- Redraw the few distortions
more like that if u want to do it on 1 img not split it up

ps: sorry if i missunderstod you.
heres my outcome: