First off you should be using initialize Animation and casting to your character class, then creating a reference for it. Try Get Pawn Owner is limited.
Use Character Ref and Character Movement Component Ref for more accurate and specific data.
Movement Speeds should be set in the Character Class. Then use Get in the animation class to use it in the anim BP.
e.g. Character Ref -> Get SomeValue
Movement Speeds should be deterministic. Your code in the character class should adjust speeds based on Action/State, then simply tell the server your action/state. The server should run the same code and produce the same result.