The calculations happen any way.
a static mesh is actually about a billion times cheaper than a skeletal one with animations.
Keep at it and in about a year you’ll “just know” why from having crashed into it.
Now as far as the BP and animation.
Rule #1
the animation blueprint shouldn’t include any code at all.
Rule #2
The pawn / actor that defines the animation should Cast once during construction and save the ABP variable to re-use elsewhere.
Now.
The ABP state machine is fine.
Make sure you have it hooked correctly to the output.
To change the value and animate, you use the value of the ABP you dragged off, and you Set the float value you defined inside the ABP from the character/pawn.
Probaboy either at the same time as you provide input or OnTick if thays how you are moving about.
bonus note.
Variables already have a default value. There’s no need to set them to 0 on load if you have the default value set to 0.