Image の値を Image2 の値にバインドする方法
<Style x:Key="ImageButton" TargetType="c:ImageButton">
<Setter Property="Image" Value="/*My image 1*/" />
<Setter Property="Image2" Value="/*My image 2*/" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="c:ImageButton">
<StackPanel Orientation="Horizontal" Height="30" Width="30">
<Image Width="30" Height="30" Source="{TemplateBinding Image}" />
</StackPanel>
</ControlTemplate>
</Setter.Value>
</Setter>
<Style.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter Property="Image" Value="{Binding to Property Image2 value}" /> // How bind value to Image2
</Trigger>
</Style.Triggers>
</Style>