You can turn off the DPI scaling by just adjusting the curve to be a scale of 1 on all resolutions. The only other option for targeting specific widgets is to apply an inverse scale of the current DPI scale to the widget, using the Scale box you could wrap it inside of, set it to manual and then apply the inverse scale.
I need to apply a fixed pixel size to only a specific widget and that through Blueprint. How would I be able to get the DPI scale in Blueprint to be able to apply the inverse scale of the current DPI to the widget?