I’m here to refresh the question.
From my side, I’d like to add that lyra only made me more confused about it when I started reading about those 2.
and here is why:
I wanted to do full leg IK on my own in docs there are simple descriptions of two
IK Rig
“Retarget and procedurally adjust animations using IK Rig and Retargeting tools”
Control Rig
“Rig and Animate characters in real-time using Control Rig”
After reading just this my first guess would be to continue with IKRig but in lyra whole leg IK is done in Control Rig. Is there a specific reason behind this or did epic just wanted to show off some features?