Although #godotengine development is moving along at a rapid pace, one of the few areas not receiving much attention is specifically #InverseKinematics (sadly the built-in node for doing IK is deprecated, and with good reason). Although there was an overhaul of skeleton modifiers, upon which IK is built, the IK itself was not fixed.
But I am happy to spread the word of a new GDExtension for IK which works well: GodotIK.
https://github.com/monxa/GodotIK