[alatar]

<s:states>
    <s:State name="normal"/>
    <s:State name="rightPerson"/>
    <s:State name="leftPerson"/>
</s:states>
 
<s:Group width="100%" height="100%">
	<s:Image id="leftImage"
			 height="100%"
			 width="100%"
			 horizontalAlign.normal="left"
			 horizontalAlign.rightPerson="left"
			 horizontalAlign.leftPerson="right"
			 depth.leftPerson="1"
			 depth.rightPerson="0"
			 source="@Embed(source='assets/personLeft.png')"/>
	<s:Image id="rightImage"
			 height="100%"
			 width="100%"
			 horizontalAlign.normal="right"
			 horizontalAlign.leftPerson="right"
			 horizontalAlign.rightPerson="left"
			 depth.leftPerson="0"
			 depth.rightPerson="1"
			 source="@Embed(source='assets/personRight.png')"/>
</s:Group>
 
<s:HGroup 
    width="100%"
    bottom="0">
    <s:Button 
        label="left"
        click="{currentState='leftPerson'}"/>
    <s:Button 
        label="normal"
        click="{currentState='normal'}"/>
    <s:Button 
        label="right"
        click="{{currentState='rightPerson'}}"/>
</s:HGroup>

Добавлено через 36 минут
Или так, если нужна анимация:

<s:states>
    <s:State name="normal"/>
    <s:State name="rightPerson"/>
    <s:State name="leftPerson"/>
</s:states>
 
<s:transitions>
	<s:Transition toState="normal">
		<s:Sequence>
			<s:SetAction target="{leftImage}" property="right"/>
			<s:SetAction target="{rightImage}" property="left"/>
			<s:Parallel>
				<s:Move target="{leftImage}" xTo="0"/>
				<s:Move target="{rightImage}" xTo="{container.width - rightImage.width}"/>
			</s:Parallel>
			<s:SetAction target="{leftImage}" property="left"/>
			<s:SetAction target="{rightImage}" property="right"/>
		</s:Sequence>
	</s:Transition>
	<s:Transition toState="leftPerson">
		<s:Sequence>
			<s:SetAction target="{leftImage}" property="left"/>
			<s:SetAction target="{rightImage}" property="left"/>
			<s:Parallel>
				<s:Move target="{leftImage}" xTo="{container.width - leftImage.width}"/>
				<s:Move target="{rightImage}" xTo="{container.width - rightImage.width}"/>
			</s:Parallel>
			<s:SetAction target="{leftImage}" property="right"/>
			<s:SetAction target="{rightImage}" property="right"/>
		</s:Sequence>
	</s:Transition>
	<s:Transition toState="rightPerson">
		<s:Sequence>
			<s:SetAction target="{leftImage}" property="right"/>
			<s:SetAction target="{rightImage}" property="right"/>
			<s:Parallel>
				<s:Move target="{leftImage}" xTo="0"/>
				<s:Move target="{rightImage}" xTo="0"/>
			</s:Parallel>
			<s:SetAction target="{leftImage}" property="left"/>
			<s:SetAction target="{rightImage}" property="left"/>
		</s:Sequence>
	</s:Transition>
</s:transitions>
 
<s:Group id="container" width="100%" height="100%">
	<s:Image id="leftImage"
			 height="100%"
			 left.normal="0"
			 left.rightPerson="0"
			 right.leftPerson="0"
			 depth.leftPerson="1"
			 depth.rightPerson="0"
			 source="@Embed(source='assets/personLeft.png')"/>
	<s:Image id="rightImage"
			 height="100%"
			 right.normal="0"
			 right.leftPerson="0"
			 left.rightPerson="0"
			 depth.leftPerson="0"
			 depth.rightPerson="1"
			 source="@Embed(source='assets/personRight.png')"/>
</s:Group>