It is related to this topic.
If you want to only move the selected area, switch to "Integral coordinates" in the toolbar above the canvas.
If you also want to resize with nearest neighbor, the fix for now is to right-click on the toolbar above the canvas, then on "Configure toolbar", then select the item "Raster Editor - Draw Mode", duplicate it (via an icon above the list) and change the "Type" to "Rasterization mode", clicking OK. Then new icons appear on the toolbar and it allows you to turn on "No smoothing" for drawing tools like the Transformation.