Select two+ bits of code, hit the assigned hotkey, watch them swap positions.

rotate-selection.py

# (c) Y_Less 2018
# MPL 1.1
# Multi-selection rotation script for Notepad++ Python Script plugin.

count = editor.getSelections()

if count > 1:
	editor.beginUndoAction()
	total = editor.getLength()
	cuts = []
	initial = True
	empty = True
	# First, collate all the selections.
	for i in xrange(count):
		(a, b) = editor.getUserCharSelection()
		c = editor.getCurrentPos()
		# Get the start of the selection, or just the cursor.
		empty = a == 0 and b == total
		cuts.append({
			'idx': c if empty else a,
			'initial': initial,
			'empty': empty,
			'start': a,
			'cursor': c,
			'length': 0 if empty else b - a,
			'text': editor.getTextRange(a, b)
		})
		initial = False
		editor.rotateSelection()
	
	# Remove the old versions.
	cuts = sorted(cuts, key = lambda k: k['idx'])
	offset = 0
	initial = 0
	for i in xrange(count):
		if cuts[i]['initial']:
			initial = i
		cuts[i]['idx'] -= offset
		cuts[i]['cursor'] -= offset
		if not cuts[i]['empty']:
			editor.deleteRange(cuts[i]['idx'], cuts[i]['length'])
		offset += cuts[i]['length'];
	
	# Insert the new versions.
	offset = 0
	for i in xrange(count):
		if not cuts[i]['empty']:
			prev = -1
			# Find the best matching string to put here.
			while cuts[i + prev]['empty']:
				prev -= 1
			cuts[i]['idx'] += offset
			editor.insertText(cuts[i]['idx'], cuts[i + prev]['text'])
			offset += cuts[i + prev]['length']
			cuts[i]['newlen'] = cuts[i + prev]['length']
	
	# Restore the selections in the order they were found.
	offset = False
	empty = True
	editor.clearSelections()
	while not offset:
		initial -= 1
		if empty:
			if cuts[initial]['empty']:
				editor.setSelection(cuts[initial]['idx'], cuts[initial]['idx'])
			else:
				editor.setSelection(cuts[initial]['idx'] + cuts[initial]['newlen'], cuts[initial]['idx'])
		else:
			if cuts[initial]['empty']:
				editor.addSelection(cuts[initial]['idx'], cuts[initial]['idx'])
			else:
				editor.addSelection(cuts[initial]['idx'] + cuts[initial]['newlen'], cuts[initial]['idx'])
		empty = False
		offset = cuts[initial]['initial']
	
	editor.endUndoAction()