that’s normal in any blend space. it’s trying to merge the 2 poses. every blendspace does this, even starter content.
The best way to do it is to just isolate the states.
walk right, walk left, walk forward, walk back.
You can maybe get away with blending the 45 degrees but I isolated those too in the end.
Overall your starting animation for the state needs to match up the second animation direction/position. if you separate the states then the engine takes care of blending the first step between the transitions and the blendspace takes over after.
also, it looks like the bone re targeting for your arm twist is set to the arm peeling it backwards. check it out