<Canvas xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
  <StackPanel>
    <Button Background="Red">
      <Button.RenderTransform>
        <SkewTransform AngleX="20" AngleY="0"/>
      </Button.RenderTransform>

                    AngleX=20, AngleY=0

    </Button>
    <Button Background="Orange">
      <Button.RenderTransform>
        <SkewTransform AngleX="-20" AngleY="0"/>
      </Button.RenderTransform>

                    AngleX=-20, AngleY=0

    </Button>
    <Button Background="Yellow">
      <Button.RenderTransform>
        <SkewTransform AngleX="0" AngleY="20"/>
      </Button.RenderTransform>

                    AngleX=0, AngleY=20

    </Button>
    <Button Background="Lime">
      <Button.RenderTransform>
        <SkewTransform AngleX="0" AngleY="-20"/>
      </Button.RenderTransform>

                    AngleX=0, AngleY=-20

    </Button>
    <Button Background="Aqua">
      <Button.RenderTransform>
        <SkewTransform AngleX="20" AngleY="20"/>
      </Button.RenderTransform>

                    AngleX=20, AngleY=20

    </Button>
  </StackPanel>
</Canvas>