For anyone who is having the same issue, I was able to find the solution was posted here by Leon Lu. Using the following code in your CreateMauiApp() method will globally change the color of your button ripple effect:
Microsoft.Maui.Handlers.ButtonHandler.Mapper.AppendToMapping("MyCustomization", (handler, view) =>
{
#if ANDROID
if (handler.PlatformView.Background is Android.Graphics.Drawables.RippleDrawable ripple )
{
//Sets the ripple color to green
ripple.SetColor(Android.Content.Res.ColorStateList.ValueOf(Android.Graphics.Color.Green));
//Hides the ripple effect
ripple.SetColor(Android.Content.Res.ColorStateList.ValueOf(Android.Graphics.Color.Transparent));
};
#endif
});