2d blendspace not blending animations properly

I am setting up a 2d blendspace (pitch and yaw being the 2 dimensions).

At pitch 0 and yaw 0, my character faces forward. This is fine.
At pitch 0 and yaw -180, my character turns to the left and ends up facing on the other side. This is also fine.

At pitch 0 and yaw 180, the character again turns to the left (rather than turning right) to face on the other side.
I tried creating an animation in the middle to fix this (i.e. an animation where the character faces 90 degrees right at pitch 0 and yaw 90), but the character turns right and then left again to face backwards!

Any help is greatly appreciated!

(I am using UE5)