Hi friends,
how can I create a Twist Control for the elbow in the fullbodyIK like in the ikchains?
Thanks

I'd say that you need to set up a mapping to a “twist” joint for that purpose. But the issue will be you will then over constrain the fullbody IK so your mileage may vary.

Thanks Edward!

Would it be possible to layer the twist on top after the full ik solve?

I just tried a toy test adding an ikchains sop after the full body ik solve and I do seem to be able to add additional twisting afterwards using that method. Just delete the tip point from the full body with a delete joints and use that as the goal and create your own twist point to feed into the ikchains sop.
Maybe there's an easier way….

Yeah, I think that's a reasonable way of going about it. You could maybe get more efficiency back if you used a Rig Attribute VOP SOP where you directly feed the transforms you want to use into a Two Bone IK VOP so that you don't need to do so much geometry manipulation.

can you share an example? i have an animated rig without goal or twist and i need to generate those for ik setup to fix feet sliding

For IK Chains? See https://www.tokeru.com/cgwiki/index.php?title=HoudiniKinefx#IK_Chain_Legs_Setup [www.tokeru.com] for an example of that.