So, I can set up a Nunchuck with Hinge Joint moving Perfectly when the nunchuck is moved slightly, but when it is moved fastly the hinge joint simulates weirdly.
when moved Slowly : -
When moved a bit fast :-
That’s “normal” stability problems with PhysX joints. You can try to reduce those (maybe search for ragdoll stability to find some tips from documentation). Alternatively you could try Articulation Bodies. These are much more stable, but have the downside of completely “exploding” and with this vanishing from scene if e.g. a too big force impacts them.
As above but also, in the first step you should try to give the solver more room to solve it by increasing the solver iterations allowed in the physics settings. That won’t help if the forces are crazy high though.