Avalonia-DataTrigger.xaml

    <!--Works-->
    <Image Source="resm:CrossTestAppAvalonia.Images.info2_blue.png" Width="32" Height="32" Margin="5"/>
    <!--Works-->
    <Image Source="resm:CrossTestAppAvalonia.Images.warning2_yellow.png" Width="32" Height="32" Margin="5"/>

    <!--Works-->
    <TextBox Name="textbox" Margin="5">
      <i:Interaction.Behaviors>
        <ia:DataTriggerBehavior Binding="{Binding MyProperty.Boolean}" ComparisonCondition="Equal" Value="true">
          <ia:ChangePropertyAction TargetObject="{Binding #textbox}" PropertyName="Text" Value="info2_blue.png" />
        </ia:DataTriggerBehavior>
        <ia:DataTriggerBehavior Binding="{Binding MyProperty.Boolean}" ComparisonCondition="Equal" Value="false">
          <ia:ChangePropertyAction TargetObject="{Binding #textbox}" PropertyName="Text" Value="warning2_yellow.png" />
        </ia:DataTriggerBehavior>
      </i:Interaction.Behaviors>
    </TextBox>
    
    <!--Stays Empty-->
    <Image Name="image" Width="32" Height="32" Margin="5">
      <i:Interaction.Behaviors>
        <ia:DataTriggerBehavior Binding="{Binding MyProperty.Boolean}" ComparisonCondition="Equal" Value="true">
          <ia:ChangePropertyAction TargetObject="{Binding #image}" PropertyName="Source" Value="resm:CrossTestAppAvalonia.Images.info2_blue.png" />
        </ia:DataTriggerBehavior>
        <ia:DataTriggerBehavior Binding="{Binding MyProperty.Boolean}" ComparisonCondition="Equal" Value="false">
          <ia:ChangePropertyAction TargetObject="{Binding #image}" PropertyName="Source" Value="resm:CrossTestAppAvalonia.Images.warning2_yellow.png" />
        </ia:DataTriggerBehavior>
      </i:Interaction.Behaviors>
    </Image>

    <!--Sets Propery Boolean true/false-->
    <Button Content="Click Me" VerticalAlignment="Center" HorizontalAlignment="Center" Click="Button_Click"/>

WPF-DataTrigger.xaml

        <Image Width="32" Height="32">
            <Image.Style>
                <Style TargetType="Image">
                    <Style.Triggers>
                        <DataTrigger Binding="{Binding MyProperty.Boolean}" Value="True">
                            <Setter Property="Source" Value="../Images/info2_blue.png"/>
                        </DataTrigger>
                        <DataTrigger Binding="{Binding MyProperty.Boolean}" Value="False">
                            <Setter Property="Source" Value="../Images/warning2_yellow.png"/>
                        </DataTrigger>
                    </Style.Triggers>
                </Style>
            </Image.Style>
        </Image>