object representing animation effect properties.
expression.EffectParameters
expression Required. An expression that returns one of the objects in the Applies To list.
Example
This example adds an effect to the main animation sequence on the first slide. This effect changes the font for the first shape to Broadway.
Sub ChangeFontName()
Dim shpText As Shape
Dim effNew As Effect
Set shpText = ActivePresentation.Slides(1).Shapes(1)
Set effNew = ActivePresentation.Slides(1).TimeLine.MainSequence _
.AddEffect(Shape:=shpText, EffectId:=msoAnimEffectChangeFont)
effNew.EffectParameters.FontName = "Broadway"
End Sub