WPF Override a trigger from a button style

I have below button style in window resources:

<Style x:Key="MyStyle" TargetType="{x:Type Button}">

    <Setter Property="BorderBrush" Value="Transparent"/>
    <Setter Property="BorderThickness" Value="0 0 0 3"/>

    <Style.Triggers>
        <Trigger Property="IsMouseOver" Value="True">
            <Setter Property="BorderBrush" Value="Orange" />
        </Trigger>
        <Trigger Property="IsPressed" Value="True">
            <Setter Property="BorderBrush" Value="Red" />
        </Trigger>         
    </Style.Triggers>

</Style>

This style is shared by two wpf buttons. But there is a button I want to show a custom color when it is pressed, the color will be green.

So in this special button I would like to override the value specified for borderbrush property in the trigger, instead of Red I would like Green.

How to do this?