Hi…
the Animation Montages got the option of setting Blend In and Blend Out speed…
This is necessary when you got a very short animation but blending would take to long…so the animation is very cut.
I now have set up a single animation that i wanna blend with another idle animation…
But it so short that it is ,because of the blend, nearly not seen 
I need to set the BlendSpeed BUT in a single animation asset there isnt that Option…
Please help EPIC.
btw. I DOnt want to use Montages…because they dont work with multiple bones somehow