Using blending tools in Sequence and AnimationBlueprint mode in skeletal mesh

I made a Sequence with a skeletal mesh and two animation blending with blending tools.
I had to add an Animation Blueprint with Slot settings and everything’s fine except the blending tools do not blend anymore. If I set Force Custom Mode it works (but no AnimBP).

Do I have to set or add something to the Animation Blueprint in order to make blending tools work alongside?

Bump! I really need to know about this.